diff --git a/doomsday/api/dd_share.h b/doomsday/api/dd_share.h
index 3f6311af6e..eb6c0092b4 100644
--- a/doomsday/api/dd_share.h
+++ b/doomsday/api/dd_share.h
@@ -702,7 +702,7 @@ enum { MX, MY, MZ };
 #define DD_BASE_POLYOBJ_ELEMENTS() \
     DD_BASE_DDMOBJ_ELEMENTS() \
 \
-    BspLeaf        *bspLeaf; /* bspLeaf in which this resides */ \
+    BspLeaf        *_bspLeaf; /* bspLeaf in which this resides */ \
     int             _indexInMap; \
     int             tag; /* Reference tag. */ \
     int             validCount; \
diff --git a/doomsday/client/include/map/line.h b/doomsday/client/include/map/line.h
index 2d9f4cc5dc..25f86c5f2e 100644
--- a/doomsday/client/include/map/line.h
+++ b/doomsday/client/include/map/line.h
@@ -31,6 +31,7 @@
 #include <de/Vector>
 
 #include "MapElement"
+#include "Polyobj"
 #include "Surface"
 #include "Vertex"
 
@@ -63,6 +64,9 @@ class Line : public de::MapElement
     /// Required sector attribution is missing. @ingroup errors
     DENG2_ERROR(MissingSectorError);
 
+    /// Required polyobj attribution is missing. @ingroup errors
+    DENG2_ERROR(MissingPolyobjError);
+
     /// The given side section identifier is invalid. @ingroup errors
     DENG2_ERROR(InvalidSectionIdError);
 
@@ -740,16 +744,27 @@ class Line : public de::MapElement
     }
 
     /**
-     * Returns @c true iff the line is part of some Polyobj.
+     * Returns @c true iff the line defines a section of some Polyobj.
+     */
+    bool definesPolyobj() const;
+
+    /**
+     * Returns the Polyobj for which the line is a defining section.
+     *
+     * @see definesPolyobj()
      */
-    bool isFromPolyobj() const;
+    Polyobj &polyobj() const;
 
     /**
-     * Mark the line as being owned by/is part of some Polyobj.
+     * Change the attributed polyobj which owns the line.
      *
-     * @param set  @c true to set, @c false to clear.
+     * @param newOwner New polyobj to attribute as the to the line. Can be
+     *                 @c 0, to clear the attribution. (Note that the polyobj
+     *                 may also represent this relationship, so the relevant
+     *                 method(s) of Polyobj will also need to be called to
+     *                 complete the job of removing this relationship.)
      */
-    void markPolyobjOwned(bool set = true);
+    void setPolyobj(Polyobj *newOwner);
 
     /**
      * Returns @c true iff the line resulted in the creation of a BSP window
diff --git a/doomsday/client/include/map/polyobj.h b/doomsday/client/include/map/polyobj.h
index 4eeb89df7f..8ecc4692a6 100644
--- a/doomsday/client/include/map/polyobj.h
+++ b/doomsday/client/include/map/polyobj.h
@@ -41,6 +41,9 @@ class Vertex;
 typedef struct polyobj_s
 {
 public:
+    /// The polyobj is not presently linked in the BSP. @ingroup errors
+    DENG2_ERROR(NotLinkedError);
+
     typedef QList<Line *> Lines;
     typedef QList<Vertex *> Vertexes;
 
@@ -55,6 +58,37 @@ typedef struct polyobj_s
     /// @note: Does nothing about the user data section.
     ~polyobj_s();
 
+    /**
+     * Returns @c true if the polyobj is presently linked in the owning GameMap.
+     */
+    bool isLinked();
+
+    /**
+     * (Re)link the polyobj in the owning GameMap. Ownership is not affected.
+     * To be called @em after rotation and/or translation to re-link the polyobj
+     * and thereby complete the process.
+     *
+     * Linking only occurs if the polyobj is not presently linked (subsequent calls
+     * are ignored).
+     */
+    void link();
+
+    /**
+     * Unlink the polyobj in the owning GameMap. To be called @em before attempting
+     * to rotate and/or translate the polyobj to initiate the process.
+     *
+     * Unlinking only occurs if the polyobj is presently linked (subsequent calls
+     * are ignored).
+     */
+    void unlink();
+
+    /**
+     * Returns the BSP leaf in which the polyobj is presently linked.
+     *
+     * @see isLinked();
+     */
+    BspLeaf &bspLeaf() const;
+
     /**
      * Returns the sound emitter for the polyobj.
      */
diff --git a/doomsday/client/src/edit_map.cpp b/doomsday/client/src/edit_map.cpp
index b8e1ceaa75..23a52250a5 100644
--- a/doomsday/client/src/edit_map.cpp
+++ b/doomsday/client/src/edit_map.cpp
@@ -1121,7 +1121,7 @@ int MPE_PolyobjCreate(int *lines, int lineCount, int tag, int sequenceType,
         if(lines[i] < 0 || lines[i] >= editMap.lines.count()) return -1;
 
         Line *line = editMap.lines[lines[i]];
-        if(line->isFromPolyobj()) return -1;
+        if(line->definesPolyobj()) return -1;
     }
 
     Polyobj *po = editMap.createPolyobj(Vector2d(originX, originY));
@@ -1133,7 +1133,7 @@ int MPE_PolyobjCreate(int *lines, int lineCount, int tag, int sequenceType,
         Line *line = editMap.lines[lines[i]];
 
         // This line belongs to a polyobj.
-        line->markPolyobjOwned();
+        line->setPolyobj(po);
         static_cast<Polyobj::Lines *>(po->_lines)->append(line);
     }
 
diff --git a/doomsday/client/src/map/bsp/partitioner.cpp b/doomsday/client/src/map/bsp/partitioner.cpp
index e217d39c54..22de94d18c 100644
--- a/doomsday/client/src/map/bsp/partitioner.cpp
+++ b/doomsday/client/src/map/bsp/partitioner.cpp
@@ -265,7 +265,7 @@ DENG2_PIMPL(Partitioner)
 
     bool lineMightHaveWindowEffect(Line const &line)
     {
-        if(line.isFromPolyobj()) return false;
+        if(line.definesPolyobj()) return false;
         if(line.hasFrontSector() && line.hasBackSector()) return false;
         if(!line.hasFrontSector()) return false;
         //if(line.hasZeroLength() || line._buildData.overlap) return false;
@@ -375,7 +375,7 @@ DENG2_PIMPL(Partitioner)
         foreach(Line *line, map->lines())
         {
             // Polyobj lines are completely ignored.
-            if(line->isFromPolyobj()) continue;
+            if(line->definesPolyobj()) continue;
 
             LineSegment *front = 0;
             coord_t angle = 0;
diff --git a/doomsday/client/src/map/gamemap.cpp b/doomsday/client/src/map/gamemap.cpp
index c54dd3916b..4b57508602 100644
--- a/doomsday/client/src/map/gamemap.cpp
+++ b/doomsday/client/src/map/gamemap.cpp
@@ -829,35 +829,13 @@ void GameMap::initPolyobjs()
 
     foreach(Polyobj *po, _polyobjs)
     {
-        // Find the center point of the polyobj.
-        Vector2d avg;
-        foreach(Line *line, po->lines())
-        {
-            avg += line->fromOrigin();
-        }
-        avg /= po->lineCount();
-
-        // Given the center point determine in which BSP leaf the polyobj resides.
-        if(BspLeaf *bspLeaf = bspLeafAtPoint(avg))
-        {
-            if(bspLeaf->hasPolyobj())
-            {
-                LOG_WARNING("Multiple polyobjs in a single BSP leaf\n"
-                            "  (BSP leaf %i, sector %i). Previous polyobj overridden.")
-                    << bspLeaf->indexInMap()
-                    << bspLeaf->sector().indexInMap();
-            }
-            bspLeaf->setFirstPolyobj(po);
-            po->bspLeaf = bspLeaf;
-        }
-
         /// @todo Is this still necessary? -ds
         /// (This data is updated automatically when moving/rotating).
         po->updateAABox();
         po->updateSurfaceTangents();
 
-        P_PolyobjUnlink(po);
-        P_PolyobjLink(po);
+        po->unlink();
+        po->link();
     }
 }
 
@@ -1055,7 +1033,7 @@ void GameMap::linkLine(Line &line)
     DENG_ASSERT(lineBlockmap != 0);
 
     // Lines of Polyobjs don't get into the blockmap (presently...).
-    if(line.isFromPolyobj()) return;
+    if(line.definesPolyobj()) return;
 
     vec2d_t origin; V2d_Copy(origin, Blockmap_Origin(lineBlockmap));
     vec2d_t cellSize; V2d_Copy(cellSize, Blockmap_CellSize(lineBlockmap));
diff --git a/doomsday/client/src/map/line.cpp b/doomsday/client/src/map/line.cpp
index 4d8c9736dd..ee862d6739 100644
--- a/doomsday/client/src/map/line.cpp
+++ b/doomsday/client/src/map/line.cpp
@@ -26,6 +26,7 @@
 #include <de/Vector>
 
 #include "m_misc.h"
+
 #include "Sector"
 #include "Vertex"
 
@@ -490,8 +491,8 @@ DENG2_PIMPL(Line)
     Side front;
     Side back;
 
-    /// @c true= the line is owned by some Polyobj.
-    bool polyobjOwned;
+    /// The polyobj which this line defines a section of, if any.
+    Polyobj *polyobj;
 
     /// Used by legacy algorithms to prevent repeated processing.
     int validCount;
@@ -511,7 +512,7 @@ DENG2_PIMPL(Line)
           length(direction.length()),
           front(*i, frontSector),
           back(*i, backSector),
-          polyobjOwned(false),
+          polyobj(0),
           validCount(0)
     {
         std::memset(mapped, 0, sizeof(mapped));
@@ -559,14 +560,24 @@ bool Line::isBspWindow() const
     return _bspWindowSector != 0;
 }
 
-bool Line::isFromPolyobj() const
+bool Line::definesPolyobj() const
+{
+    return d->polyobj != 0;
+}
+
+Polyobj &Line::polyobj() const
 {
-    return d->polyobjOwned;
+    if(d->polyobj)
+    {
+        return *d->polyobj;
+    }
+    /// @throw Line::MissingPolyobjError Attempted with no polyobj attributed.
+    throw Line::MissingPolyobjError("Line::polyobj", "No polyobj is attributed");
 }
 
-void Line::markPolyobjOwned(bool set)
+void Line::setPolyobj(Polyobj *newOwner)
 {
-    d->polyobjOwned = set;
+    d->polyobj = newOwner;
 }
 
 Line::Side &Line::side(int back)
diff --git a/doomsday/client/src/map/p_dmu.cpp b/doomsday/client/src/map/p_dmu.cpp
index 8067501d1d..1dd2d51384 100644
--- a/doomsday/client/src/map/p_dmu.cpp
+++ b/doomsday/client/src/map/p_dmu.cpp
@@ -2245,16 +2245,14 @@ DENG_EXTERN_C void P_SetPolyobjCallback(void (*func) (struct mobj_s *, void *, v
 DENG_EXTERN_C void P_PolyobjUnlink(Polyobj *po)
 {
     if(!po) return;
-    /// @todo Do not assume polyobj is from the CURRENT map.
-    theMap->unlinkPolyobj(*po);
+    po->unlink();
 }
 
 #undef P_PolyobjLink
 DENG_EXTERN_C void P_PolyobjLink(Polyobj *po)
 {
     if(!po) return;
-    /// @todo Do not assume polyobj is from the CURRENT map.
-    theMap->linkPolyobj(*po);
+    po->link();
 }
 
 #undef P_PolyobjByID
diff --git a/doomsday/client/src/map/polyobj.cpp b/doomsday/client/src/map/polyobj.cpp
index a8f8a869f0..85e75336a5 100644
--- a/doomsday/client/src/map/polyobj.cpp
+++ b/doomsday/client/src/map/polyobj.cpp
@@ -26,9 +26,11 @@
 #include "de_base.h"
 
 #include "map/p_maptypes.h"
-#include "render/r_main.h" // validCount
+#include "map/gamemap.h"
 #include "HEdge"
 
+#include "render/r_main.h" // validCount
+
 #include "map/polyobj.h"
 
 using namespace de;
@@ -75,7 +77,7 @@ polyobj_s::polyobj_s(de::Vector2d const &origin_)
 {
     origin[VX] = origin_.x;
     origin[VY] = origin_.y;
-    bspLeaf = 0;
+    _bspLeaf = 0;
     tag = 0;
     validCount = 0;
     dest[0] = dest[1] = 0;
@@ -109,6 +111,62 @@ void Polyobj::setCollisionCallback(void (*func) (mobj_t *mobj, void *line, void
     collisionCallback = func;
 }
 
+bool Polyobj::isLinked()
+{
+    return _bspLeaf != 0;
+}
+
+void Polyobj::unlink()
+{
+    if(_bspLeaf)
+    {
+        /// @todo Do not assume polyobj is from the CURRENT map.
+        theMap->unlinkPolyobj(*this);
+        _bspLeaf = 0;
+    }
+}
+
+void Polyobj::link()
+{
+    if(!_bspLeaf)
+    {
+        theMap->linkPolyobj(*this);
+
+        // Find the center point of the polyobj.
+        Vector2d avg;
+        foreach(Line *line, lines())
+        {
+            avg += line->fromOrigin();
+        }
+        avg /= lineCount();
+
+        // Given the center point determine in which BSP leaf the polyobj resides.
+        /// @todo Do not assume polyobj is from the CURRENT map.
+        if(BspLeaf *bspLeaf = theMap->bspLeafAtPoint(avg))
+        {
+            if(bspLeaf->hasPolyobj())
+            {
+                LOG_WARNING("Multiple polyobjs in a single BSP leaf\n"
+                            "  (BSP leaf %i, sector %i). Previous polyobj overridden.")
+                    << bspLeaf->indexInMap()
+                    << bspLeaf->sector().indexInMap();
+            }
+            bspLeaf->setFirstPolyobj(this);
+            _bspLeaf = bspLeaf;
+        }
+    }
+}
+
+BspLeaf &Polyobj::bspLeaf() const
+{
+    if(_bspLeaf)
+    {
+        return *_bspLeaf;
+    }
+    /// @throw Polyobj::NotLinkedError Attempted while the polyobj is not linked to the BSP.
+    throw Polyobj::NotLinkedError("Polyobj::bspLeaf", "Polyobj is not presently linked in the BSP");
+}
+
 ddmobj_base_t &Polyobj::soundEmitter()
 {
     return *reinterpret_cast<ddmobj_base_t *>(this);
@@ -261,7 +319,7 @@ bool Polyobj::move(Vector2d const &delta)
     LOG_AS("Polyobj::move");
     //LOG_DEBUG("Applying delta %s to [%p]") << delta.asText() << this;
 
-    P_PolyobjUnlink(this);
+    unlink();
     {
         VertexCoords::iterator prevCoordsIt = static_cast<VertexCoords *>(_prevPts)->begin();
         foreach(Vertex *vertex, uniqueVertexes())
@@ -285,14 +343,14 @@ bool Polyobj::move(Vector2d const &delta)
 
         updateAABox();
     }
-    P_PolyobjLink(this);
+    link();
 
     // With translation applied now determine if we collided with anything.
     if(mobjIsBlockingPolyobj(*this))
     {
         //LOG_DEBUG("Blocked by mobj, undoing...");
 
-        P_PolyobjUnlink(this);
+        unlink();
         {
             VertexCoords::const_iterator prevCoordsIt = static_cast<VertexCoords *>(_prevPts)->constBegin();
             foreach(Vertex *vertex, uniqueVertexes())
@@ -311,7 +369,7 @@ bool Polyobj::move(Vector2d const &delta)
 
             updateAABox();
         }
-        P_PolyobjLink(this);
+        link();
 
         return false;
     }
@@ -344,7 +402,7 @@ bool Polyobj::rotate(angle_t delta)
     //LOG_DEBUG("Applying delta %u (%f) to [%p]")
     //    << delta << (delta / float( ANGLE_MAX ) * 360) << this;
 
-    P_PolyobjUnlink(this);
+    unlink();
     {
         uint fineAngle = (angle + delta) >> ANGLETOFINESHIFT;
 
@@ -375,14 +433,14 @@ bool Polyobj::rotate(angle_t delta)
         updateAABox();
         angle += delta;
     }
-    P_PolyobjLink(this);
+    link();
 
     // With rotation applied now determine if we collided with anything.
     if(mobjIsBlockingPolyobj(*this))
     {
         //LOG_DEBUG("Blocked by mobj, undoing...");
 
-        P_PolyobjUnlink(this);
+        unlink();
         {
             VertexCoords::const_iterator prevCoordsIt = static_cast<VertexCoords *>(_prevPts)->constBegin();
             foreach(Vertex *vertex, uniqueVertexes())
@@ -402,7 +460,7 @@ bool Polyobj::rotate(angle_t delta)
             updateAABox();
             angle -= delta;
         }
-        P_PolyobjLink(this);
+        link();
 
         return false;
     }
diff --git a/doomsday/client/src/render/r_fakeradio.cpp b/doomsday/client/src/render/r_fakeradio.cpp
index d0ea87f071..10a5dc27ce 100644
--- a/doomsday/client/src/render/r_fakeradio.cpp
+++ b/doomsday/client/src/render/r_fakeradio.cpp
@@ -41,7 +41,7 @@ static zblockset_t *shadowLinksBlockSet;
 
 bool Rend_RadioLineCastsShadow(Line const &line)
 {
-    if(line.isFromPolyobj()) return false;
+    if(line.definesPolyobj()) return false;
     if(line.isSelfReferencing()) return false;
 
     // Lines with no other neighbor do not qualify for shadowing.
diff --git a/doomsday/client/src/render/rend_fakeradio.cpp b/doomsday/client/src/render/rend_fakeradio.cpp
index 20ed5cc029..e7acc776cf 100644
--- a/doomsday/client/src/render/rend_fakeradio.cpp
+++ b/doomsday/client/src/render/rend_fakeradio.cpp
@@ -1257,7 +1257,7 @@ static void writeShadowSection2(ShadowEdge const &leftEdge, ShadowEdge const &ri
 static void writeShadowSection(int planeIndex, Line::Side &side, float shadowDark)
 {
     DENG_ASSERT(side.hasSections());
-    DENG_ASSERT(!side.line().isFromPolyobj());
+    DENG_ASSERT(!side.line().definesPolyobj());
 
     if(!(shadowDark > .0001)) return;
 
diff --git a/doomsday/client/src/render/rend_main.cpp b/doomsday/client/src/render/rend_main.cpp
index faaadf2935..53e879c167 100644
--- a/doomsday/client/src/render/rend_main.cpp
+++ b/doomsday/client/src/render/rend_main.cpp
@@ -1303,7 +1303,7 @@ static float wallSectionEdgeLightLevelDelta(Line::Side &side, int section, int e
     // Is delta smoothing disabled?
     if(!rendLightWallAngleSmooth) return delta;
     // ...always for polyobj lines (no owner rings).
-    if(side.line().isFromPolyobj()) return delta;
+    if(side.line().definesPolyobj()) return delta;
 
     /**
      * Smoothing is enabled, so find the neighbor side for the specified edge
@@ -1636,7 +1636,7 @@ static bool writeWallSection(SectionEdge const &leftEdge, SectionEdge const &rig
         // Render FakeRadio for this section?
         if((flags & WSF_ADD_RADIO) && !(parm.flags & RPF_SKYMASK) &&
            !(parm.glowing > 0) && currentSectorLightLevel > 0 &&
-           !line.isFromPolyobj())
+           !line.definesPolyobj())
         {
             Rend_RadioUpdateForLineSide(side);
 
@@ -2922,7 +2922,7 @@ void Rend_RenderSurfaceVectors()
     Vector3f origin;
     foreach(HEdge *hedge, theMap->hedges())
     {
-        if(!hedge->hasLineSide() || hedge->line().isFromPolyobj())
+        if(!hedge->hasLineSide() || hedge->line().definesPolyobj())
             continue;
 
         if(!hedge->hasBspLeaf() || !hedge->bspLeaf().hasSector())
@@ -2998,7 +2998,7 @@ void Rend_RenderSurfaceVectors()
 
     foreach(Polyobj *polyobj, theMap->polyobjs())
     {
-        Sector const &sector = polyobj->bspLeaf->sector();
+        Sector const &sector = polyobj->bspLeaf().sector();
         float zPos = sector.floor().height() + (sector.ceiling().height() - sector.floor().height())/2;
 
         foreach(Line *line, polyobj->lines())
@@ -3204,8 +3204,8 @@ static int drawVertex1(Line *li, void *context)
 
         if(alpha > 0)
         {
-            coord_t bottom = po->bspLeaf->sector().floor().visHeight();
-            coord_t top    = po->bspLeaf->sector().ceiling().visHeight();
+            coord_t bottom = po->bspLeaf().sector().floor().visHeight();
+            coord_t top    = po->bspLeaf().sector().ceiling().visHeight();
 
             if(devVertexBars)
                 drawVertexBar(vtx, bottom, top, MIN_OF(alpha, .15f));
@@ -3224,7 +3224,7 @@ static int drawVertex1(Line *li, void *context)
 
         pos[VX] = vtx->origin().x;
         pos[VY] = vtx->origin().y;
-        pos[VZ] = po->bspLeaf->sector().floor().visHeight();
+        pos[VZ] = po->bspLeaf().sector().floor().visHeight();
 
         dist3D = V3d_Distance(pos, eye);
 
@@ -3279,7 +3279,7 @@ void Rend_Vertexes()
             if(!own) continue;
 
             // Ignore polyobj vertexes.
-            if(own->line().isFromPolyobj()) continue;
+            if(own->line().definesPolyobj()) continue;
 
             float alpha = 1 - M_ApproxDistance(vOrigin[VX] - vertex->origin().x,
                                                vOrigin[VZ] - vertex->origin().y) / MAX_VERTEX_POINT_DIST;
@@ -3309,7 +3309,7 @@ void Rend_Vertexes()
         if(!own) continue;
 
         // Ignore polyobj vertexes.
-        if(own->line().isFromPolyobj()) continue;
+        if(own->line().definesPolyobj()) continue;
 
         coord_t dist = M_ApproxDistance(vOrigin[VX] - vertex->origin().x,
                                        vOrigin[VZ] - vertex->origin().y);
@@ -3340,7 +3340,7 @@ void Rend_Vertexes()
             if(!own) continue;
 
             // Ignore polyobj vertexes.
-            if(own->line().isFromPolyobj()) continue;
+            if(own->line().definesPolyobj()) continue;
 
             pos[VX] = vertex->origin().x;
             pos[VY] = vertex->origin().y;
@@ -3803,7 +3803,7 @@ static void Rend_RenderBoundingBoxes()
     {
         foreach(Polyobj const *polyobj, theMap->polyobjs())
         {
-            Sector const &sec = polyobj->bspLeaf->sector();
+            Sector const &sec = polyobj->bspLeaf().sector();
             coord_t width  = (polyobj->aaBox.maxX - polyobj->aaBox.minX)/2;
             coord_t length = (polyobj->aaBox.maxY - polyobj->aaBox.minY)/2;
             coord_t height = (sec.ceiling().height() - sec.floor().height())/2;