Summary: This note introduces a measure of parallelism for activity networks, and we suggest its relevance to concurrent engineering efforts. The importance of the ability to judge the degree of parallelism in a concurrent engineering project is discussed. Then, a brief review of the existing measures of parallelism is provided. Due to the drawbacks of some of these measures, a new measure, Omega, is introduced and its performance is compared to the other measures. The results indicate that Omega is an excellent measure of parallelism, particularly for application in concurrent engineering.