Several high quality crystals of AgGaSe2 have been grown utilizing the vertical Bridgman technique. Boule sizes were typically 20 mm in diameter and 80 mm long. The optical transmission of AgGaSe2 samples annealed in the presence of Ag2Se3 is essentially reflection-limited over most of its transmission ranges. Calculations were made of the angular tuning characteristics of infrared frequency doublers using type Ⅰ and type Ⅱ processes. The frequency doublers of 10. 6 μm radiation for type Ⅰ phase matching were built from these crystals. The phase matching angle measured experimentally is 56.1°, and the acceptance angle parameter ΔΘ·L is 1.04°·cm in a frequency doubling experiment of the 10.6 μm radiation from a TEA CO2 laser.