A series of borate NLO crystals, BBO, LBO, CBO, KBBF, SBBO, CLBO, YCOB, GdCOB, GdYCOB, KAB and BABF are often employed for UV light generation. However, the search for new NLO crystals with enhanced performance has been a continuous process. There are two key factors which involve in identifying suitable new UV NLO crystals. Firstly, designing a suitable structure that possesses desired UV NLO properties. Secondly, the possibility of growing these crystals with suitable growth method. In this report, the structural aspects of the above mentioned crystals will be compared. New structural models and new technology which are designed based on these comparisons will be discussed. Finally, the details of the growth experiments and the difficulties associated with the growth will be discussed. Reports of growth RSBO and MB(8)O(13)(.)2H(2)O(M = Ca2+, Sr2+) and their NLO properties will be presented for the first time. (c) 2004 Elsevier B.V. All rights reserved.