The Atacama Large Millimeter/submillimeter Array (ALMA) is an international facility at an advanced stage of construction in the Atacama region of northern Chile. ALMA will consist of two arrays of high-precision antennas: one made up of twelve 7-meter diameter antennas operating in closely-packed configurations of about 50m in diameter, and the other of up to sixty-four 12-meter antennas arranged in configurations with diameters ranging from about 150 meters to 15 km. There will be four more 12-meter antennas to provide the "zero-spacing" information, which is critical for making accurate images of extended objects. The antennas will be equipped with sensitive millimeter-wave receivers covering most of the frequency range 84 to 950 GHz. State-of-the-art microwave, digital, photonic and software systems will capture the signals, transfer them to the central building and correlate them, while maintaining accurate synchronization. ALMA will provide images of a wide range of astronomical objects with great sensitivity and very high spectral resolution. The images will have much higher "fidelity" than those from existing mm/submm telescopes. This paper gives an update on the status of construction and on progress with the testing and scientific commissioning.

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