Four major discussions are presented related to economic issues involved with property rights as applied to computer software and data bases. The first discussion qualitatively compares the relative incentives to computer software producers found in alternative regimes of copyright and trade secrecy. The latter is found to have certain dysfunctional qualities which copyright might ameliorate. The second discussion providing a critical view of exemptions from copyright for broad classes of users arrives at the conclusion that exemptions decrease economic efficiency which would be increased through user charges. The third section creates a model of software production and protection and indicates that the term of copyright protection for software should be very short. The final discussion analyzes the trade-off between the scope of protection and the length of time for which the protection lasts. Appendices include mathematical derivations of the optimal protection period for a linear demand curve and a nonlinear demand curve. (Author/CMV)