Scientists are still looking for cheap, compact, blue or UV lasers for high-density optical storage. The small size, excellent beam quality, low price and negligible operating costs of possible nitride diode lasers make them today's best potential laser source in this wavelength range. But there are still some unsolved technological problems in their manufacturing and even unanswered fundamental questions concerning their theory. They are discussed in the present paper. In particular, nature of the laser transition itself is analyzed, problems with an efficient and controllable doping of nitride layers are describes as well as degradation mechanisms and methods of their suppression are presented. Afterwards, some possible structures of nitride lasers are proposed.