The authors present an application of a simulated annealing global optimization method for the structural design of doublet lenses in accordance with a prespecified set of Gaussian characteristics and primary aberration targets. This approach eliminates the need for any prescription for the starting point in the optimization procedure. An identical approach is implemented for the structural design of both cemented and broken contact doublets. Boundaries for the design variables are taken care of by constraining the random walk of this Monte Carlo algorithm entirely within the feasible configuration space. For the sake of accelerating convergence in optimization, few modifications of the basic simulated annealing technique are attempted. Some illustrative examples are given.