diff --git a/src/engine/Queue.h b/src/engine/Queue.h
new file mode 100644
index 0000000000..69081b8716
--- /dev/null
+++ b/src/engine/Queue.h
@@ -0,0 +1,78 @@
+/*
+ * FILE:
+ * Queue.h
+ *
+ * DESCRIPTION:
+ * Provide simple FIFO/LIFO cost-basis accounting support.
+ *
+ * RESTRICTIONS:
+ * -- Does not support use with mixed currencies.
+ * -- Does not check for or warn mixed currency use.
+ * -- Does not allow pushhead after a pophead has occured.
+ *
+ * HISTORY:
+ * created by Linas Vepstas January 1999
+ * Copyright (c) 1999 Linas Vepstas
+ */
+/********************************************************************\
+ * This program is free software; you can redistribute it and/or    *
+ * modify it under the terms of the GNU General Public License as   *
+ * published by the Free Software Foundation; either version 2 of   *
+ * the License, or (at your option) any later version.              *
+ *                                                                  *
+ * This program is distributed in the hope that it will be useful,  *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of   *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the    *
+ * GNU General Public License for more details.                     *
+ *                                                                  *
+ * You should have received a copy of the GNU General Public License*
+ * along with this program; if not, write to the Free Software      *
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.        *
+\********************************************************************/
+
+#ifndef __XACC_QUEUE_H__
+#define __XACC_QUEUE_H__
+
+#include "Transaction.h"
+
+typedef struct _Queue Queue;
+
+/*
+ * The xaccQueuePushHead() routine pushes a split onto the head 
+ *    of the queue.
+ *
+ * The xaccQueuePopTailShares() routine removes the indicated
+ *    number of shares from the bottom of the queue.  If the queue
+ *    does not contain that many shares, it dequeues all of the 
+ *    shares. This routine returns the actual number of shares dequeued.
+ *    Use this routine for FIFO accounting.
+ *
+ * The xaccQueuePopTailValue() routine removes the indicated
+ *    value from the bottom of the queue.  If the value of the queue is less
+ *    than this amount, the value of the queue is set to zero, and the
+ *    actual value poped is returned.
+ *    Use this routine for FIFO accounting.
+ *
+ * The xaccQueuePopHeadShares() and xaccQueuePopHeadValue() routines
+ *    behave in the same way as the *Tail* versions, except that they act
+ *    on the head of the queue.  Use these routines for LIFO accounting.
+ *
+ * The xaccQueueGetValue() routine returns the value of the queue.
+ * The xaccQueueGetShares() routine returns the number of shares in the queue.
+ */
+
+Queue * xaccMallocQueue (void);
+void xaccInitQueue (Queue *q);
+void xaccFreeQueue (Queue *q);
+
+void xaccQueuePushHead (Queue *q, Split *s);
+
+double xaccQueuePopHeadShares (Queue *, double);
+double xaccQueuePopHeadValue (Queue *, double);
+double xaccQueuePopTailShares (Queue *, double);
+double xaccQueuePopTailValue (Queue *, double);
+
+double xaccQueueGetValue (Queue *);
+double xaccQueueGetShares (Queue *);
+
+#endif /* __XACC_QUEUE_H__ */