Book excerpt: Constrained optimization problems: basic concepts; Posynomial geometric programming; Practical aspect of G.P. problem-solving; Signomial geometric programming; Tactics for handling posynomial programs with loose constraints and degreess of difficulty; Extensions of geometric programming to non-standard forms; Reversed constraints and transformations to posynomial programs; Solutions of signomial programs through condensation; The underlying primal structure and its use in computation; Selected applications of geometric programming;