diff --git a/lib/dns/byaddr.c b/lib/dns/byaddr.c
new file mode 100644
index 0000000000..7cd26176b0
--- /dev/null
+++ b/lib/dns/byaddr.c
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2000  Internet Software Consortium.
+ * 
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
+ * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
+ * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ */
+
+#include <config.h>
+
+#include <isc/assertions.h>
+#include <isc/error.h>
+#include <isc/result.h>
+#include <isc/task.h>
+#include <isc/util.h>
+#include <isc/mem.h>
+#include <isc/mutex.h>
+
+#include <dns/byaddr.h>
+#include <dns/resolver.h>
+#include <dns/view.h>
+
+/*
+ * XXXRTH  We could use a static event...
+ */
+
+struct dns_byaddr {
+	/* Unlocked. */
+	unsigned int		magic;
+	isc_mutex_t		lock;
+	dns_view_t *		view;
+	/* Locked by lock. */
+	dns_byaddrevent_t *	event;
+};
+
+#define BYADDR_MAGIC			0x42794164U	/* ByAd. */
+#define VALID_BYADDR(b)			((b) != NULL && \
+					 (b)->magic == BYADDR_MAGIC)
+
+#ifdef notyet
+
+isc_result_t
+dns_byaddr_create(isc_netaddr_t *address, dns_view_t *view,
+		  unsigned int options, isc_task_t *task,
+		  isc_taskaction_t action, void *arg, dns_byaddr_t **byaddrp)
+{
+	isc_result_t result;
+	dns_byaddr_t *byaddr;
+	
+	byaddr = isc_mem_get(view->mctx, sizeof *byaddr);
+	if (byaddr == NULL)
+		return (ISC_R_NOMEMORY);
+
+	result = isc_mutex_init(&byaddr->lock);
+	if (result != ISC_R_SUCCESS)
+		goto cleanup_byaddr;
+	byaddr->view = NULL;
+	dns_view_attach(view, &byaddr->view);
+	
+	return (ISC_R_SUCCESS);
+
+ cleanup_lock:
+	isc_mutex_destroy(&byaddr->lock);
+
+ cleanup_byaddr:
+	isc_mem_put(view->mctx, byaddr, sizeof *byaddr);
+
+	return (result);
+}
+
+void
+dns_byaddr_cancel(dns_byaddr_t *byaddr) {
+}
+
+void
+dns_byaddr_destroy(dns_byaddr_t **byaddrp) {
+}
+
+#endif
diff --git a/lib/dns/include/dns/byaddr.h b/lib/dns/include/dns/byaddr.h
new file mode 100644
index 0000000000..d0eb1d2587
--- /dev/null
+++ b/lib/dns/include/dns/byaddr.h
@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2000  Internet Software Consortium.
+ * 
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
+ * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
+ * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ */
+
+#ifndef DNS_BYADDR_H
+#define DNS_BYADDR_H 1
+
+/*****
+ ***** Module Info
+ *****/
+
+/*
+ * DNS ByAddr
+ *
+ * The byaddr module provides reverse lookup services for IPv4 and IPv6
+ * addresses.
+ *
+ * MP:
+ *	The module ensures appropriate synchronization of data structures it
+ *	creates and manipulates.
+ *
+ * Reliability:
+ *	No anticipated impact.
+ *
+ * Resources:
+ *	<TBS>
+ *
+ * Security:
+ *	No anticipated impact.
+ *
+ * Standards:
+ *	RFCs:	1034, 1035, 2181, <TBS>
+ *	Drafts:	<TBS>
+ */
+
+#include <isc/types.h>
+#include <isc/lang.h>
+#include <isc/event.h>
+#include <isc/netaddr.h>
+
+#include <dns/types.h>
+#include <dns/name.h>
+#include <dns/fixedname.h>
+#include <dns/result.h>
+
+ISC_LANG_BEGINDECLS
+
+typedef struct dns_byaddrevent {
+	ISC_EVENT_COMMON(struct dns_byaddrevent);
+	dns_byaddr_t *			byaddr;
+	isc_result_t			result;
+	dns_fixedname_t			name;
+} dns_byaddrevent_t;
+
+isc_result_t
+dns_byaddr_create(isc_netaddr_t *address, dns_view_t *view,
+		  unsigned int options, isc_task_t *task,
+		  isc_taskaction_t action, void *arg, dns_byaddr_t **byaddrp);
+/*
+ * Find the domain name of 'address'.
+ *
+ * Requires:
+ *
+ *	'address' is a valid IPv4 or IPv6 address.
+ *
+ *	'view' is a valid view which has a resolver.
+ *
+ *	'task' is a valid task.
+ *
+ *	byaddrp != NULL && *byaddrp == NULL
+ *
+ * Returns:
+ *
+ *	ISC_R_SUCCESS
+ *	ISC_R_NOMEMORY
+ *
+ *	Any resolver-related error (e.g. ISC_R_SHUTTINGDOWN) may also be
+ *	returned.
+ */
+
+void
+dns_byaddr_cancel(dns_byaddr_t *byaddr);
+/*
+ * Cancel 'byaddr'.
+ *
+ * Notes:
+ *
+ *	If 'byaddr' has not completed, post its BYADDRDONE event with a
+ *	result code of ISC_R_CANCELED.
+ *
+ * Requires:
+ *
+ *	'byaddr' is a valid byaddr.
+ */
+
+void
+dns_byaddr_destroy(dns_byaddr_t **byaddrp);
+/*
+ * Destroy 'byaddr'.
+ *
+ * Requires:
+ *
+ *	'*byaddrp' is a valid byaddr.
+ *
+ *	The caller has received the BYADDRDONE event (either because the
+ *	byaddr completed or because dns_byaddr_cancel() was called).
+ *
+ * Ensures:
+ *
+ *	*byaddrp == NULL.
+ */
+
+ISC_LANG_ENDDECLS
+
+#endif /* DNS_BYADDR_H */