The PISA assessment instruments for students' scientific literacy in 2000, 2003, and 2006 have each consisted of units made up of a real world context involving Science and Technology, about which students are asked a number of cognitive and affective questions. This article discusses a number of issues from this use of S&T contexts in PISA and the implications they have for the current renewed interest in context-based science education. Suitably chosen contexts can engage both boys and girls. Secondary analyses of the students' responses using the contextual sets of items as the unit of analysis provides new information about the levels of performance in PISA 2006 Science. Embedding affective items in the achievement test did not lead to gender/context interactions of significance, and context interactions were less than competency ones. A number of implications for context-based science teaching and learning are outlined and the PISA 2006 Science test is suggested as a model for its assessment. (Contains 3 tables.)