diff --git a/doomsday/engine/portable/include/gamemap.h b/doomsday/engine/portable/include/gamemap.h
index 70dc86fddf..91d7dac729 100644
--- a/doomsday/engine/portable/include/gamemap.h
+++ b/doomsday/engine/portable/include/gamemap.h
@@ -112,7 +112,9 @@ typedef struct gamemap_s {
     nodepile_t mobjNodes, lineNodes; // All kinds of wacky links.
     nodeindex_t* lineLinks; // Indices to roots.
 
-    float globalGravity; // Gravity for the current map.
+    float globalGravity; // The defined gravity for this map.
+    float effectiveGravity; // The effective gravity for this map.
+
     int ambientLightLevel; // Ambient lightlevel for the current map.
 
     /// Current LOS trace state.
@@ -132,6 +134,31 @@ const char* GameMap_OldUniqueId(GameMap* map);
 
 void GameMap_Bounds(GameMap* map, float* min, float* max);
 
+/**
+ * Retrieve the current effective gravity multiplier for this map.
+ *
+ * @param map  GameMap instance.
+ * @return  Effective gravity multiplier for this map.
+ */
+float GameMap_Gravity(GameMap* map);
+
+/**
+ * Change the effective gravity multiplier for this map.
+ *
+ * @param map  GameMap instance.
+ * @param gravity  New gravity multiplier.
+ * @return  Same as @a map for caller convenience.
+ */
+GameMap* GameMap_SetGravity(GameMap* map, float gravity);
+
+/**
+ * Return the effective gravity multiplier to that originally defined for this map.
+ *
+ * @param map  GameMap instance.
+ * @return  Same as @a map for caller convenience.
+ */
+GameMap* GameMap_RestoreGravity(GameMap* map);
+
 /**
  * Retrieve an immutable copy of the LOS trace line.
  *
diff --git a/doomsday/engine/portable/include/p_mapdata.h b/doomsday/engine/portable/include/p_mapdata.h
index 4efa0f3301..e7bfad32f0 100644
--- a/doomsday/engine/portable/include/p_mapdata.h
+++ b/doomsday/engine/portable/include/p_mapdata.h
@@ -187,8 +187,6 @@ extern surfacelist_t* movingSurfaceList;
 extern surfacelist_t* decoratedSurfaceList;
 extern surfacelist_t* glowingSurfaceList;
 
-extern float mapGravity;
-
 #include "gamemap.h"
 
 // The current map.
diff --git a/doomsday/engine/portable/src/dam_main.c b/doomsday/engine/portable/src/dam_main.c
index 4b1f0114e8..dc17083c93 100644
--- a/doomsday/engine/portable/src/dam_main.c
+++ b/doomsday/engine/portable/src/dam_main.c
@@ -600,6 +600,8 @@ boolean DAM_AttemptMapLoad(const Uri* uri)
                 map->ambientLightLevel = 0;
             }
 
+            map->effectiveGravity = map->globalGravity;
+
             // @todo should be called from P_LoadMap() but R_InitMap requires the
             //       theMap to be set first.
             P_SetCurrentMap(map);
diff --git a/doomsday/engine/portable/src/dd_main.c b/doomsday/engine/portable/src/dd_main.c
index 5694757c5c..1cb14977b0 100644
--- a/doomsday/engine/portable/src/dd_main.c
+++ b/doomsday/engine/portable/src/dd_main.c
@@ -2215,7 +2215,8 @@ void* DD_GetVariable(int ddvalue)
         return &cplrThrustMul;*/
 
     case DD_GRAVITY:
-        return &mapGravity;
+        valueF = theMap? GameMap_Gravity(theMap) : 0;
+        return &valueF;
 
     case DD_TORCH_RED:
         return &torchColor[CR];
@@ -2289,7 +2290,7 @@ void DD_SetVariable(int ddvalue, void *parm)
             return;*/
 
         case DD_GRAVITY:
-            mapGravity = *(float*) parm;
+            if(theMap) GameMap_SetGravity(theMap, *(float*) parm);
             return;
 
         case DD_PSPRITE_OFFSET_X:
diff --git a/doomsday/engine/portable/src/gamemap.c b/doomsday/engine/portable/src/gamemap.c
index e41ade5391..ede8698955 100644
--- a/doomsday/engine/portable/src/gamemap.c
+++ b/doomsday/engine/portable/src/gamemap.c
@@ -54,6 +54,26 @@ void GameMap_Bounds(GameMap* map, float* min, float* max)
     max[VY] = map->bBox[BOXTOP];
 }
 
+float GameMap_Gravity(GameMap* map)
+{
+    assert(map);
+    return map->effectiveGravity;
+}
+
+GameMap* GameMap_SetGravity(GameMap* map, float gravity)
+{
+    assert(map);
+    map->effectiveGravity = gravity;
+    return map;
+}
+
+GameMap* GameMap_RestoreGravity(GameMap* map)
+{
+    assert(map);
+    map->effectiveGravity = map->globalGravity;
+    return map;
+}
+
 const divline_t* GameMap_TraceLOS(GameMap* map)
 {
     assert(map);
diff --git a/doomsday/engine/portable/src/p_data.c b/doomsday/engine/portable/src/p_data.c
index d9551712e7..ffdd415d71 100644
--- a/doomsday/engine/portable/src/p_data.c
+++ b/doomsday/engine/portable/src/p_data.c
@@ -64,8 +64,6 @@ surfacelist_t* movingSurfaceList = NULL;
 surfacelist_t* decoratedSurfaceList = NULL;
 surfacelist_t* glowingSurfaceList = NULL;
 
-float mapGravity;
-
 GameMap* theMap = NULL;
 
 // Bad texture list
@@ -139,8 +137,6 @@ void P_SetCurrentMap(GameMap* map)
         decoratedSurfaceList = 0;
         glowingSurfaceList = 0;
 
-        mapGravity = 0;
-
         theMap = map;
         return;
     }
@@ -161,8 +157,6 @@ void P_SetCurrentMap(GameMap* map)
     decoratedSurfaceList = &map->decoratedSurfaceList;
     glowingSurfaceList = &map->glowingSurfaceList;
 
-    mapGravity = map->globalGravity;
-
     theMap = map;
 }
 
diff --git a/doomsday/engine/portable/src/p_particle.c b/doomsday/engine/portable/src/p_particle.c
index 3df1590986..48856a6d54 100644
--- a/doomsday/engine/portable/src/p_particle.c
+++ b/doomsday/engine/portable/src/p_particle.c
@@ -1083,7 +1083,8 @@ static void P_MoveParticle(ptcgen_t* gen, particle_t* pt)
     P_SpinParticle(gen, pt);
 
     // Changes to momentum.
-    pt->mov[VZ] -= FixedMul(FLT2FIX(mapGravity), st->gravity);
+    /// @fixme Do not assume generator is from the CURRENT map.
+    pt->mov[VZ] -= FixedMul(FLT2FIX(GameMap_Gravity(theMap)), st->gravity);
 
     // Vector force.
     if(stDef->vectorForce[VX] != 0 || stDef->vectorForce[VY] != 0 ||
diff --git a/doomsday/plugins/common/src/d_netcl.c b/doomsday/plugins/common/src/d_netcl.c
index 581bd24255..eb2b03d8cf 100644
--- a/doomsday/plugins/common/src/d_netcl.c
+++ b/doomsday/plugins/common/src/d_netcl.c
@@ -139,6 +139,7 @@ void NetCl_UpdateGameState(Reader* msg)
     }
 
     // Set gravity.
+    /// @fixme This is a map-property, not a global property.
     DD_SetVariable(DD_GRAVITY, &gsGravity);
 
     // Camera init included?