diff --git a/include/grp.h b/include/grp.h
new file mode 100644
index 0000000..a55f18c
--- /dev/null
+++ b/include/grp.h
@@ -0,0 +1,21 @@
+#ifndef _GRP_H
+#define _GRP_H
+
+#include <types/gid_t.h>
+#include <types/size_t.h>
+
+struct group {
+  char *  gr_name;
+  gid_t   gr_gid;
+  char ** gr_mem;
+};
+
+void endgrent(void);
+struct group * getgrent(void);
+struct group * getgrgid(gid_t);
+int getgrgid_r(gid_t, struct group *, char *, size_t, struct group **);
+struct group * getgrnam(const char *);
+int getgrnam_r(const char *, struct group *, char *, size_t, struct group **);
+void setgrent(void);
+
+#endif
\ No newline at end of file