To measure what determines people's attitudes, definitions, or decisions, surveys increasingly ask respondents to judge vignettes. A vignette typically describes a hypothetical situation or object as having various attributes (dimensions). In factorial surveys, the values (levels) of dimensions are experimentally varied, so that their impact on respondents' judgments can be estimated. Drawing on the literature in cognitive psychology and survey methodology, we examine two research questions: Does the order in which dimensions are presented impact the vignette evaluations and change substantive conclusions? Under which conditions are order effects mostly likely to occur? Using data from a web survey of 300 students, we analyze several possible moderators: features of the vignette design, characteristics of respondents, and interactions between these features. Results show that strong order effects can occur, but only when the vignettes are of a minimum complexity or respondents show a low attitude certainty.