The first section of four essays approaches expert witnessing from both broad philosophical and narrow empirical bases. Two essays examine the historical and philosophical origins of expert witnessing in general, and a third relates the field of expert witnessing directly to criminological issues. The fourth essay is an empirically based study of a series of practical concerns that uniquely confront the expert. The unique demands of expert witnessing are further examined in the four essay of the second section. The first essay examines the relationships between the personal-biographic characteristics of 120 experts and their experiences in court. The other three essays relate many of these same demands to the authors' own areas of expertise. The issues explored include police research and police misconduct, death penalty research, pornography, and criminal justice hiring practices. The final four essays explore the personal and professional costs of appearing as an expert witness. The final three essays question the relevance of social science experts in court. The responses to questions regarding the role of social scientists in court range from measured optimism to determined negativism. 53-item bibliography, listing of cases and codes, and subject index.