diff --git a/skeletons/NULL.c b/skeletons/NULL.c
new file mode 100644
index 0000000..9027e2c
--- /dev/null
+++ b/skeletons/NULL.c
@@ -0,0 +1,51 @@
+/*-
+ * Copyright (c) 2003 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#include <NULL.h>
+#include <BOOLEAN.h>	/* Implemented in terms of BOOLEAN type */
+
+/*
+ * NULL basic type description.
+ */
+static ber_tlv_tag_t asn1_DEF_NULL_tags[] = {
+	(ASN_TAG_CLASS_UNIVERSAL | (5 << 2))
+};
+asn1_TYPE_descriptor_t asn1_DEF_NULL = {
+	"NULL",
+	asn_generic_no_constraint,
+	BOOLEAN_decode_ber,	/* Implemented in terms of BOOLEAN */
+	NULL_encode_der,	/* Special handling of DER encoding */
+	NULL_print,
+	BOOLEAN_free,
+	0, /* Use generic outmost tag fetcher */
+	asn1_DEF_NULL_tags,
+	sizeof(asn1_DEF_NULL_tags)/sizeof(asn1_DEF_NULL_tags[0]),
+	1,	/* Single UNIVERSAL tag may be implicitly overriden */
+	0	/* Always in primitive form */
+};
+
+der_enc_rval_t
+NULL_encode_der(asn1_TYPE_descriptor_t *sd, void *ptr,
+	int tag_mode, ber_tlv_tag_t tag,
+	asn_app_consume_bytes_f *cb, void *app_key) {
+	der_enc_rval_t erval;
+
+	erval.encoded = der_write_tags(sd, 0, tag_mode, tag, cb, app_key);
+	if(erval.encoded == -1) {
+		erval.failed_type = sd;
+		erval.structure_ptr = ptr;
+	}
+
+	return erval;
+}
+
+int
+NULL_print(asn1_TYPE_descriptor_t *td, const void *sptr, int ilevel,
+	asn_app_consume_bytes_f *cb, void *app_key) {
+	if(sptr) {
+		return cb("<present>", 9, app_key);
+	} else {
+		return cb("<absent>", 8, app_key);
+	}
+}