Engineered binding proteins are provided. In some cases, the parent protein corresponding to the engineered protein has a three-layer swiveling .beta./.beta./.alpha. domain. In other cases, the parent protein corresponding to the engineered protein has a rubredoxin-like fold. At least one portion of the primary sequence of the engineered protein is determined by an engineering scheme. In some case, the engineered protein is characterized by an ability to bind to a compound that the parent protein does not bind. In some cases, the parent protein is derived from a domain of a chaperonin or a rubredoxin. One form of engineering scheme used is a randomization scheme. A method for making libraries of engineered proteins, all based on a single parent protein is provided. Methods to identify proteins that bind to compounds of interest in libraries of engineered libraries are provided. An array of engineered proteins immobilized on a support is provided. Each engineered protein in the array is a chaperonin domain or a rubredoxin that has been subjected to an engineering scheme.