One general area that determines lawyer competence in knowledge of law, legal institutions, and the lawyering process; amd the second general category that determines competence is the skills necessary to practice law, including legal-factual analysis, legal research, communication and interpersonal skill, organizational skill, and fact development skill; the third category that determines attorney competence is character, attitude, and values. The literature on prior research on the effectiveness of criminal lawyers deals in four major areas; (1) theoretical studies of lawyers' values and loyalties, (2) client surveys, (3) surveys of judges and lawyers, and (4) cross-sectional studies of case outcomes. The Phoenix study of criminal defense attorney competence focuses on trial preparation, plea bargaining, and sentencing. These are preparatory tasks that principally involve fact investigation, including witness interviews, discovery from the government, visits to the scene of an offense, and interaction with the probation officer who prepares the presentence investigation report. The study first interviewed 173 defense attorneys practicing in Maricopa County concerning investigations conducted in four of their most recent cases. In the study's second phase, probation officers monitored over 500 felony cases during 30 days to record the activities of defense lawyers in seeking favorable sentences for their clients. Finally, over 50 prosecutors were interviewed to obtain data related to defense attorneys' discovery and plea bargaining practices. The interview forms are appended. For an analysis of the study findings, see NCJ 86945-47.