In Census 2000, the Census Bureau will make special efforts to reach people who do not have a usual place of residence. As part of Service-Based Enumeration (SBE) operations, enumerations of the clients of regularly scheduled food vans will be conducted on a specified date. After the enumerations are completed and responses are collected, the data will be checked for internal and external duplication.

Since many of the clients using food van services will have a usual place of residence, it will be necessary to collect address information from them to facilitate unduplication. However, for clients without a usual place of residence, a request for address information could be very confusing and may slow down the time-sensitive data collection process.

This paper explores the circumstances under which asking for address information is appropriate. It focuses on the responses given on a self-administered questionnaire by the clients of two New York City food van runs to “place where you stay” and address questions. The data show that the “place where you stay” question can be used as a screen for determining when to ask the address question.