This study's purpose was twofold: to investigate the nature of police patrol work in a community policing context and to field-test data collection instruments designed for systematic social observation. The project, conducted in Richmond, Virginia, where its police department was in the third year of a five-year plan to implement community policing, was designed as a case study of one police department's experience with community policing, focusing on officers in the patrol division. A team of eight researchers conducted observations with the police officers in the spring and summer of 1992. A total of 120 officers were observed during 125 observation sessions. Observers accompanied officers throughout their regular work shifts, taking brief field notes on officers' activities and encounters with the public. All of an observed officer's time during the shift was accounted for by either encounters or activities. Within 15 hours of the completion of the ridealong, the observer prepared a detailed narrative account of events that occurred during the ridealong and coded key items associated with these events. The study generated five nested quantitative datasets that can be linked by common variables. Part 1, Ridealong Data, provides information pertinent to the 125 observation sessions or "rides." Part 2, Activity Data, focuses on 5,576 activities conducted by officers when not engaged in encounters. Data in Part 3, Encounter Data, describe 1,098 encounters with citizens during the ridealongs. An encounter was defined as a communication between officers and citizens that took over one minute, involved more than three verbal exchanges between an officer and a citizen, or involved significant physical contact between the officer and citizen. Part 4, Citizen Data, provides data relevant to each of the 1,630 citizens engaged by police in the encounters. Some encounters involved more than one citizen. Part 5, Arrest Data, was constructed by merging Parts 1, 3, and 4, and provides information on 451 encounters that occurred during the ridealongs in which the citizen was suspected of some criminal mischief. All identification variables in this collection were created by the researchers for this project. Variables from Part 1 include date, start time, end time, unit, and beat assignment of the observation session, and the primary officer's and secondary officer's sex, race/ethnicity, years as an officer, months assigned to precinct and beat, hours of community policing training, and general orientation to community policing. Variables in Part 2 specify the time the activity began and ended, who initiated the activity, type, location, and visibility of the activity, involvement of the officer's supervisor during the activity, and if the activity involved problem-solving, or meeting with citizens or other community organizations. Part 3 variables include time encounter began and ended, who initiated the encounter, primary and secondary officer's energy level and mood before the encounter, problem as radioed by dispatcher, and problem as it appeared at the beginning of the encounter and at the end of the encounter. Information on the location of the encounter includes percent of time at initial location, visibility, officer's prior knowledge of the initial location, and if the officer anticipated violence at the scene. Additional variables focus on the presence of a supervisor, other police officers, service personnel, bystanders, and participants, if the officer filed or intended to file a report, if the officer engaged in problem-solving, and factors that influenced the officer's actions. Citizen information in Part 4 includes sex, age, and race/ethnicity of the citizen, role in the encounter, if the citizen appeared to be of low income, under the use of alcohol or drugs, or appeared to have a mental disorder or physical injury or illness, if the citizen was representing an establishment, if the citizen lived, worked, or owned property in the police beat, and if the citizen had a weapon. Also presented are various aspects of the police-citizen interaction, such as evidence considered by the officer, requests and responses to each other, and changes in actions during the encounter. Variables in Part 5 record the officer's orientation toward community policing, if the suspect was arrested or cited, if the offense was serious or drug-related, amount of evidence, if the victim requested that the suspect be arrested, if the victim was white, Black, and of low income, and if the suspect represented an organization. Information on the suspect includes gender, race, sobriety level, if of low income, if 19 years old or less, if actively resistant, if the officer knew the suspect adversarially, and if the suspect demonstrated conflict with others. Some items were recoded for the particular analyses for which the Arrest Data were constructed.