The mathematical computational method of genetic algorithms is frequently useful in solving optimization problems in systems with many parameters, for example, a search for suitable parameters of a given problem that achieves a stated purpose. The method searches for these parameters in an efficient parallel way, and has some analogies with evolution. There are other optimization methods available, such as stimulated annealing, but we shall use genetic algorithms. We shall present three different problems that give an indication of the diversity of applications. We begin with a very short primer on genetic algorithms, which can be omitted if the reader has some knowledge of this subject. Genetic algorithms (GAs) work with a coding of a parameter set, which in the field of chemical kinetics may consist of a number of parameters, such as rate coefficients; variables and constraints, such as concentrations; and other quantities such as chemical species. Binary coding for a parameter is done as follows. Suppose we have a rate coefficient = 9.08 × 10−7; then if we write that rate coefficient as 10−P , with −10 ≤ P ≤ 10, a binary coding with string length of 16 bits is given by . . . P = 10 − 20 R /(216 − 1) (10.1) . . . where 0 ≤ R ≤ 216 − 1. Since P = 6.04 we have R = 12,971, or R = 0011001010101010 to the base 2. Thus the value of the rate coefficient is encoded in a single bit string, called a chromosome. For the solution of a given problem an optimization criterion must be chosen. With a given choice of parameters this criterion is calculated; the comparison of that calculation with the goal set for the criterion gives a fitness value for that set of parameters. If the fitness is adequate but not sufficient, when both are selected by prior choice, for any individual, then retain that individual for the next generation. Reject individuals below that choice. Select individuals for the next generation with a probability proportional to the fitness value from a roulette wheel on which the slot size is proportional to the fitness value. Notice that genetic algorithms use probabilistic, not deterministic, transition rules.