diff --git a/plot/include/plot/plot.h b/plot/include/plot/plot.h
index 90c0f1f..367d6e8 100644
--- a/plot/include/plot/plot.h
+++ b/plot/include/plot/plot.h
@@ -77,7 +77,7 @@ class Plot
 
     Plot( Context context );
 
-    Plot( AbstractPlot &plot );
+    Plot( const AbstractPlot &plot );
 
     Plot &AxisStyle( Style style, const std::vector< std::pair< std::string, std::string >> &params = {} );
 
diff --git a/plot/src/plot.cpp b/plot/src/plot.cpp
index 6adb2ab..f7e9daa 100644
--- a/plot/src/plot.cpp
+++ b/plot/src/plot.cpp
@@ -30,7 +30,7 @@
 
 #include <assert.h>
 
-PLOTLIB_INLINE Plot::Plot( AbstractPlot &plot )
+PLOTLIB_INLINE Plot::Plot( const AbstractPlot &plot )
     : Plot()
 {
     AddPlot( plot );