Construction industry recognizes the necessity to manage is business from viewpoint of processes, and consider developing, evaluating and improving standard processes as important managerial target. SW-CMM provides basic framework for this process management. However, appropriate tailoring and adjustment are essential for SW-CMM concept to be applied to construction business. SW-CMM makes construction manager understand the capability of business process, based on which the priority of process improvement is judged. The capability is prescribed by common features. This paper introduces the basic frame for diagnosing construction business processes with SW-CMM, and presents the case study of analysing processes focusing on communication management.