This paper examines the beliefs and practices about the integration of grammar and skills teaching reported by 176 English language teachers from 18 countries. Teachers completed a questionnaire which elicited beliefs about grammar teaching generally as well as specific beliefs and reported practices about the integration of grammar and skills teaching. Teachers expressed strong beliefs in the need to avoid teaching grammar in isolation and reported high levels of integration of grammar in their practices. This study also examines how teachers conceptualize integration and the sources of evidence they draw on in assessing the effectiveness of their instructional practices in teaching grammar. The major findings for this paper stem from an analysis of these two issues. A range of ways in which teachers understood integration are identified and classified into two broad orientations which we label temporal and contextual. An analysis of the evidence which teachers cited in making judgements about the effectiveness of their grammar teaching practices showed that it was overwhelmingly practical and experiential and did not refer in any explicit way to second language acquisition theory. Given the volume of available theory about L2 grammar teaching generally and integration specifically, the lack of direct reference to such evidence in teachers' accounts is noteworthy.