diff --git a/src/hydro.h b/src/hydro.h
index abb49d35b204bbaf986f502d796883e7eb778e7f..78ae7d178ff93b01fa2eeebe09f34b718ce9a826 100644
--- a/src/hydro.h
+++ b/src/hydro.h
@@ -23,8 +23,10 @@
 #include "../config.h"
 
 /* Local headers. */
+#include "const.h"
 #include "hydro_properties.h"
 #include "kernel_hydro.h"
+#include "part.h"
 
 /* Import the right functions */
 #if defined(MINIMAL_SPH)
diff --git a/src/hydro_properties.c b/src/hydro_properties.c
index bd8328946d4bfd078bd10b439e96b35dce457c49..5e3c9f3f461e56f7b91efc7ded48ba1414d3bfcd 100644
--- a/src/hydro_properties.c
+++ b/src/hydro_properties.c
@@ -26,6 +26,7 @@
 
 /* Local headers. */
 #include "adiabatic_index.h"
+#include "equation_of_state.h"
 #include "common_io.h"
 #include "dimension.h"
 #include "error.h"