The article's first part describes how the composition of police workforces has changed over the past several decades, noting that they have become more diverse regarding race, gender, and sexual orientation. The second part of the article assesses the effects of the changes that have already occurred in the demographics of law enforcement workforces. The effects are divided into three categories: competency effects, which pertain to the ways in which minority officers, female officers, and openly gay and lesbian officers may have distinctive sets of abilities; community effects, which involve ways in which the demographic diversity of a police agency may influence its relationships with the community it serves; and organizational effects, which refer to ways in which the workforce diversity may impact the internal dynamics of the department itself. In the latter category of effects, there is increasing evidence that demographic diversity in departments has weakened both occupational solidarity and the social isolation of the police. This trend has not undermined police effectiveness and has enhanced police interactions with the community both on and off duty. The last part of the article examines some of the broader sociopolitical implications of the demographic diversity of police departments. These pertain to the effectiveness and need for affirmative action policies, litigation as an effective strategy for social reform, personnel diversification as a factor in enhancing prospects for police reforms, and improvement in how police deal with a demographically diverse community. 107 footnotes