diff --git a/pdal/PointTable.cpp b/pdal/PointTable.cpp
index e9e0214606..8b8a879ceb 100644
--- a/pdal/PointTable.cpp
+++ b/pdal/PointTable.cpp
@@ -47,6 +47,19 @@ MetadataNode BasePointTable::privateMetadata(const std::string& name)
 }
 
 
+void BasePointTable::addSpatialReference(const SpatialReference& spatialRef)
+{
+    auto it = std::find(m_spatialRefs.begin(), m_spatialRefs.end(), spatialRef);
+
+    // If not found, add to the beginning.
+    if (it == m_spatialRefs.end())
+        m_spatialRefs.push_front(spatialRef);
+    // If not the first element, move the found element to the front.
+    else if (it != m_spatialRefs.begin())
+        m_spatialRefs.splice(m_spatialRefs.begin(), m_spatialRefs, it);
+}
+
+
 void SimplePointTable::setFieldInternal(Dimension::Id id, PointId idx,
     const void *value)
 {
diff --git a/pdal/PointTable.hpp b/pdal/PointTable.hpp
index 211a381103..e5b6b7b1ff 100644
--- a/pdal/PointTable.hpp
+++ b/pdal/PointTable.hpp
@@ -34,7 +34,7 @@
 
 #pragma once
 
-#include <set>
+#include <list>
 #include <vector>
 
 #include "pdal/SpatialReference.hpp"
@@ -48,6 +48,7 @@ namespace pdal
 
 class PDAL_DLL BasePointTable : public PointContainer
 {
+    FRIEND_TEST(PointTable, srs);
     friend class PointView;
 
 protected:
@@ -75,8 +76,7 @@ class PDAL_DLL BasePointTable : public PointContainer
     }
     void clearSpatialReferences()
         { m_spatialRefs.clear(); }
-    void addSpatialReference(const SpatialReference& srs)
-        { m_spatialRefs.insert(srs); }
+    void addSpatialReference(const SpatialReference& srs);
     bool spatialReferenceUnique() const
         { return m_spatialRefs.size() == 1; }
     SpatialReference spatialReference() const
@@ -103,7 +103,7 @@ class PDAL_DLL BasePointTable : public PointContainer
 
 protected:
     MetadataPtr m_metadata;
-    std::set<SpatialReference> m_spatialRefs;
+    std::list<SpatialReference> m_spatialRefs;
     PointLayout& m_layoutRef;
 };
 typedef BasePointTable& PointTableRef;
diff --git a/test/unit/PointTableTest.cpp b/test/unit/PointTableTest.cpp
index aa4ebe1d4f..a8073a22ab 100644
--- a/test/unit/PointTableTest.cpp
+++ b/test/unit/PointTableTest.cpp
@@ -38,7 +38,8 @@
 #include <io/LasReader.hpp>
 #include "Support.hpp"
 
-using namespace pdal;
+namespace pdal
+{
 
 TEST(PointTable, resolveType)
 {
@@ -178,3 +179,28 @@ TEST(PointTable, userView)
     EXPECT_TRUE(called);
 }
 
+TEST(PointTable, srs)
+{
+   SpatialReference srs1("GEOGCS[\"WGS 84\",DATUM[\"WGS_1984\",SPHEROID[\"WGS 84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]],AUTHORITY[\"EPSG\",\"6326\"]],PRIMEM[\"Greenwich\",0,AUTHORITY[\"EPSG\",\"8901\"]],UNIT[\"degree\",0.0174532925199433,AUTHORITY[\"EPSG\",\"9122\"]],AUTHORITY[\"EPSG\",\"4326\"]]");
+
+   SpatialReference srs2("PROJCS[\"WGS 84 / UTM zone 17N\",GEOGCS[\"WGS 84\",DATUM[\"WGS_1984\",SPHEROID[\"WGS 84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]],AUTHORITY[\"EPSG\",\"6326\"]],PRIMEM[\"Greenwich\",0],UNIT[\"degree\",0.0174532925199433],AUTHORITY[\"EPSG\",\"4326\"]],PROJECTION[\"Transverse_Mercator\"],PARAMETER[\"latitude_of_origin\",0],PARAMETER[\"central_meridian\",-81],PARAMETER[\"scale_factor\",0.9996],PARAMETER[\"false_easting\",500000],PARAMETER[\"false_northing\",0],UNIT[\"metre\",1,AUTHORITY[\"EPSG\",\"9001\"]],AUTHORITY[\"EPSG\",\"32617\"]]");
+
+    PointTable table;
+
+    table.addSpatialReference(srs1);
+    table.addSpatialReference(srs1);
+    EXPECT_TRUE(table.spatialReferenceUnique());
+    EXPECT_EQ(table.anySpatialReference(), srs1);
+
+    table.addSpatialReference(srs2);
+    EXPECT_FALSE(table.spatialReferenceUnique());
+    EXPECT_EQ(table.anySpatialReference(), srs2);
+    EXPECT_EQ(table.m_spatialRefs.size(), 2u);
+
+    table.addSpatialReference(srs1);
+    EXPECT_FALSE(table.spatialReferenceUnique());
+    EXPECT_EQ(table.anySpatialReference(), srs1);
+    EXPECT_EQ(table.m_spatialRefs.size(), 2u);
+}
+
+} // namespace