This study examined street robbery patterns in Philadelphia, Pennsylvania, from the years 2009 to 2011 to determine whether the effects of potentially criminogenic places are different across different periods of the day. Census block (N = 13,164) street robbery counts across four periods (6:45 a.m. to 9:59 a.m., 10:00 a.m. to 4:29 p.m., 4:30 p.m. to 9:14 p.m., and 9:15 p.m. to 6:44 a.m.) were modeled with 12 different potentially criminogenic places, 3 measures of illicit markets, 4 compositional control variables, and spatially lagged versions of the 12 potentially criminogenic places and population using simultaneously estimated negative binomial regression models. Differences in the magnitudes of the parameter estimates across the time periods were assessed with Wald tests. Overall, the patterns across the four models were mostly consistent with the effects hypothesized based on the study's crime pattern theory and time-geography theoretical frame; yet differences in the magnitudes of the coefficients were less pronounced than hypothesized. Overall, the results provide moderate support for the crime pattern theory and time-geography explanation of spatial-temporal robbery patterns; however, numerous points are raised for future crime and place research.An axiom of the crime and place literature is that certain types of places are important predictors of the spatial distribution of crime (P. L. Brantingham and P. J. Brantingham, 1999; P. J. Brantingham and P. L. Brantingham, 1991;Wilcox and Eck, 2011) and even can be used to forecast crime events (Caplan, Kennedy, and Miller, 2010). The link among certain types of places and higher crime levels has been empirically demonstrated for many different types of places, such as high schools, bars and taverns, convenience stores, public transportation stations, check-cashing stores, liquor stores, parks, and public housing communities (