diff --git a/user-doc/Installation.txt b/user-doc/Installation.txt
index ef961ead8d9352e81972ed19001270ae934a0569..b6fe1ac726bb9296d7400977f6fae1aed177c809 100644
--- a/user-doc/Installation.txt
+++ b/user-doc/Installation.txt
@@ -486,13 +486,24 @@ Compile it:
 \warning ALMOST needs SQLITE3 and  GZIP installed on your computer.
 \warning ALMOST cannot be installed in the same folder of the source code, use --prefix to install it in a different folder
 
+On Linux:
+
 \verbatim
 > ./configure --prefix="wherever you want it" CXXFLAGS="-O3 -fPIC" CFLAGS="-O3 -fPIC" LIBS=-llapack 
 > make
 > make install
 \endverbatim
-Configure can complain about lapack and RDCs but it doesn't matter.
+
+On OSX:
+\verbatim
+> ./configure --prefix="wherever you want it" CXXFLAGS="-O3" CFLAGS="-O3" 
+> make
+> make install
+\endverbatim
+
+The configuration can complain about lapack and RDCs but it doesn't matter.
 Sometimes ALMOST can give errors related to the automake tools. To fix them it is often enough to execute
+
 \verbatim
 > autoreconf -fi
 > automake