diff --git a/docs/latex/wx/sysopt.tex b/docs/latex/wx/sysopt.tex
index 08eb57b3a8..a8b885da0a 100644
--- a/docs/latex/wx/sysopt.tex
+++ b/docs/latex/wx/sysopt.tex
@@ -88,6 +88,15 @@ A reasonable default is used if not specified.}
 \twocolitem{motif.largebuttons}{If 1, uses a bigger default size for wxButtons.}
 \end{twocollist}
 
+\wxheading{All}
+
+\twocolwidtha{7cm}
+\begin{twocollist}\itemsep=0pt
+\twocolitem{{\bf Option}}{{\bf Value}}
+\twocolitem{sizer.desktopmargin.x}{The horizontal margin to subtract from the desktop size when computing the maximum top-level window size in wxSizer::Fit.}
+\twocolitem{sizer.desktopmargin.y}{The vertical margin to subtract from the desktop size when computing the maximum top-level window size in wxSizer::Fit.}
+\end{twocollist}
+
 The compile-time option to include or exclude this functionality
 is wxUSE\_SYSTEM\_OPTIONS.
 
diff --git a/src/common/sizer.cpp b/src/common/sizer.cpp
index 3b1a77280a..364b173dc1 100644
--- a/src/common/sizer.cpp
+++ b/src/common/sizer.cpp
@@ -31,6 +31,10 @@
     #include "wx/toplevel.h"
 #endif // WX_PRECOMP
 
+#if wxUSE_SYSTEM_OPTIONS
+#include "wx/sysopt.h"
+#endif
+
 #include "wx/listimpl.cpp"
 
 
@@ -792,6 +796,13 @@ wxSize wxSizer::Fit( wxWindow *window )
             }
 
             sizeMax = wxDisplay(disp).GetClientArea().GetSize();
+
+#if wxUSE_SYSTEM_OPTIONS
+            int marginX = wxSystemOptions::GetOptionInt(wxT("sizer.desktopmargin.x"));
+            int marginY = wxSystemOptions::GetOptionInt(wxT("sizer.desktopmargin.y"));
+            sizeMax.x -= marginX;
+            sizeMax.y -= marginY;
+#endif
         }
     }