diff --git a/btree.h b/btree.h
index 777ce56..40247ea 100644
--- a/btree.h
+++ b/btree.h
@@ -1,8 +1,9 @@
 #ifndef BTREE_H
 #define BTREE_H
 
-#include "btypes.h"  // integer definitions
-#include "btree_vfs.h" // bTreeVFS class
+#include "btypes.h"     // integer definitions
+#include "btree_vfs.h"  // bTreeVFS class
+#include "btree_key.h"  // bTree key functions
 
 enum treeTypes { BT_CUSTOM, BT_PCHAR, BT_STRING, BT_SINGLE, BT_DOUBLE, BT_INT32, BT_INT64 };
 
@@ -52,10 +53,6 @@
   treeTypes treeType;
 } __attribute__((__packed__));
 
-typedef int (*compareKeyFunc)(void *, void *);
-typedef void (*copyKeyProc)(void *, void *);
-typedef int (*keySizeFunc)(void *);
-
 class bTree {
  protected:
   compareKeyFunc compareKey;
diff --git a/btree_key.cpp b/btree_key.cpp
new file mode 100644
index 0000000..04d45b8
--- /dev/null
+++ b/btree_key.cpp
@@ -0,0 +1,125 @@
+#include "btree_key.h"
+#include "btypes.h"
+#include <string.h>
+
+int 
+compareKeyNull(void *, void *) {
+  return 0;
+} // compareKeyNull
+
+int 
+compareKeyString(void * , void * ) { 
+  return 0;
+} // compareKeyString
+
+int 
+compareKeyPChar(void * key1, void * key2) {
+  return strcmp((char *)key1, (char *)key2);
+} // compareKeyPChar
+
+int 
+compareKeySingle(void * , void * ) {
+  return 0;
+} // compareKeySingle
+
+int 
+compareKeyDouble(void * , void * ) {
+  return 0;
+} // compareKeyDouble
+
+int 
+compareKeyInt32(void * , void * ) {
+  return 0;
+} // compareKeyInt32
+
+int 
+compareKeyInt64(void * , void * ) {
+  return 0;
+} // compareKeyInt64
+
+/*
+ *  CopyKey functions
+ */
+
+void 
+copyKeyNull(void *, void *) {
+  return;
+} // copyKeyNull
+
+void 
+copyKeyString(void *, void *) {
+
+} // copyKeyString
+
+void 
+copyKeyPChar(void *, void *) {
+  
+} // copyKeyPChar
+
+void 
+copyKeySingle(void * srcKey, void * destKey) {
+  if ((srcKey == NULL) || (destKey == NULL)) return;
+  *(float *)destKey = *(float *)srcKey;
+} // copyKeySingle
+
+void 
+copyKeyDouble(void * srcKey, void * destKey) {
+  if ((srcKey == NULL) || (destKey == NULL)) return;
+  *(double *)destKey = *(double *)srcKey;
+} // copyKeyDouble
+
+void 
+copyKeyInt32(void * srcKey, void * destKey) {
+  if ((srcKey == NULL) || (destKey == NULL)) return;
+  *(int32 *)destKey = *(int32 *)srcKey;
+} // copyKeyInt32
+
+void 
+copyKeyInt64(void * srcKey, void * destKey) {
+  if ((srcKey == NULL) || (destKey == NULL)) return;
+  *(int64 *)destKey = *(int64 *)srcKey;
+} // copyKeyInt64
+
+/* 
+ *  KeySize functions
+ */
+
+int 
+keySizeNull(void *) {
+  return 0;
+} // keySizeNull
+
+int 
+keySizeString(void * key) {
+  const char * charKey = static_cast<const char *>(key);
+  if (charKey == NULL) return 0;
+  return ((int)charKey[0]+1);
+} // keySizeString
+
+int 
+keySizePChar(void * key) {
+  const char * charKey = static_cast<const char *>(key);
+  if (charKey == NULL) return 0;
+  return (strlen(charKey)+1);
+} // keySizePChar
+
+int 
+keySizeSingle(void *) {
+  return sizeof(float);
+} // keySizeSingle
+
+int 
+keySizeDouble(void *) {
+  return sizeof(double);
+}
+
+int 
+keySizeInt32(void *) {
+  return sizeof(int32);
+}
+
+int 
+keySizeInt64(void *) {
+  return sizeof(int64); 
+}
+
diff --git a/btree_key.h b/btree_key.h
new file mode 100644
index 0000000..b7f4101
--- /dev/null
+++ b/btree_key.h
@@ -0,0 +1,32 @@
+#ifndef BTREE_KEY_H
+#define BTREE_KEY_H
+
+typedef int (*compareKeyFunc)(void *, void *);
+typedef void (*copyKeyProc)(void *, void *);
+typedef int (*keySizeFunc)(void *);
+
+int compareKeyNull(void *, void *);
+int compareKeyString(void *, void *);
+int compareKeyPChar(void *, void *);
+int compareKeySingle(void *, void *);
+int compareKeyDouble(void *, void *);
+int compareKeyInt32(void *, void *);
+int compareKeyInt64(void *, void *);
+
+void copyKeyNull(void *, void *);
+void copyKeyString(void *, void *);
+void copyKeyPChar(void *, void *);
+void copyKeySingle(void *, void *);
+void copyKeyDouble(void *, void *);
+void copyKeyInt32(void *, void *);
+void copyKeyInt64(void *, void *);
+
+int keySizeNull(void *);
+int keySizeString(void *);
+int keySizePChar(void *);
+int keySizeSingle(void *);
+int keySizeDouble(void *);
+int keySizeInt32(void *);
+int keySizeInt64(void *);
+
+#endif