AL is a high-level programming system for specification of manipulatory tasks such as assembly of an object from parts. AL includes an ALGOL-like source language, a translator for converting programs into runnable code, and a runtime system for controlling manipulators and other devices. The system includes advanced features for describing individual motions of manipulators, for using sensory information, and for describing assembly algorithms in terms of common domain-specific primitives. This document describes the design of AL, which is currently being implemented as a successor to the Stanford WAVE system.