Abstract: A method of operating a clinical analyzer wherein the analyzer includes a plurality of reaction locations divided into two groups. Predetermined operations are performed on the first and second groups during corresponding processing cycles. A process that is common to both cycles is performed simultaneously for reaction locations in the first and second groups during only one of the cycles. The other of the cycles can thus accommodate operations unique to particular tests that would not otherwise be available on the analyzer. The common process may be washing of adjacent reaction locations included in the first and second groups.