diff --git a/src/genmap.c b/src/genmap.c
index ced1b95e7..757c49eda 100644
--- a/src/genmap.c
+++ b/src/genmap.c
@@ -167,21 +167,41 @@ GenmapElements GenmapGetElements(GenmapHandle h) {
   return (GenmapElements) h->elementArray.ptr;
 }
 
+void GenmapSetElements(GenmapHandle h, GenmapElements elements) {
+  h->elementArray.ptr = elements;
+}
+
 GenmapComm GenmapGetLocalComm(GenmapHandle h) {
   return h->local;
 }
 
+void GenmapSetLocalComm(GenmapHandle h, GenmapComm c) {
+  h->local = c;
+}
+
 GenmapComm GenmapGetGlobalComm(GenmapHandle h) {
   return h->global;
 }
 
+void GenmapSetGlobalComm(GenmapHandle h, GenmapComm c) {
+  h->global = c;
+}
+
 GenmapInt GenmapGetNLocalElements(GenmapHandle h) {
   return h->header->lelt;
 }
 
+void GenmapSetNLocalElements(GenmapHandle h, GenmapInt localElements) {
+  h->header->lelt = localElements;
+}
+
 GenmapLong GenmapGetNGlobalElements(GenmapHandle h) {
   return h->header->nel;
 }
+
+void GenmapSetNGlobalElements(GenmapHandle h, GenmapLong globalElements) {
+  h->header->nel = globalElements;
+}
 //
 // GenmapMalloc, Realloc, Calloc and Free
 //
diff --git a/src/genmap.h b/src/genmap.h
index 5f0c7b73e..7e40d06d6 100644
--- a/src/genmap.h
+++ b/src/genmap.h
@@ -52,10 +52,19 @@ int GenmapRegisterReader(char *name, int (*Create)(GenmapHandle h));
 // Genmap header helper functions
 //
 GenmapElements GenmapGetElements(GenmapHandle h);
+void GenmapSetElements(GenmapHandle h, GenmapElements elements);
+
 GenmapComm GenmapGetLocalComm(GenmapHandle h);
+void GenmapSetLocalComm(GenmapHandle h, GenmapComm c);
+
 GenmapComm GenmapGetGlobalComm(GenmapHandle h);
+void GenmapSetGlobalComm(GenmapHandle h, GenmapComm c);
+
 GenmapInt GenmapGetNLocalElements(GenmapHandle h);
+void GenmapSetNLocalElements(GenmapHandle h, GenmapInt localElements);
+
 GenmapLong GenmapGetNGlobalElements(GenmapHandle h);
+void GenmapSetNGlobalElements(GenmapHandle h, GenmapLong globalElements);
 //
 // GenmapCommExternal
 //