The abilities and limitations of the operator in control room work are discussed in more detail in this chapter. We aim to give concrete data that can be of use in the design of control rooms. Much of the background discussion, motivation, and other important aspects is omitted in order to bring about a fully comprehensive solution, as it is not possible to summarise these in a handbook of this type. For more detailed information, the reader should refer to the specialist psychological or sociopsychological literature, or consult ergonomic or psychology experts in the eld (for example, Stevens, 1975; Hamilton, 1983; Salvendy, 1986).