The focus of this study is to examine opinions about the implementation of the curriculum integration of mathematics and science (CIMAS). For this purpose, the study aims to explore possible mathematics topics for CIMAS and reach a consensus about advantages, disadvantages, and limitations of implementation of CIMAS. To achieve the consensus, a Delphi study was conducted with experts with regard to curriculum integration. The experts were university academics and school teachers in Ankara. The research produced a number of key findings: almost each unit in mathematics can be integrated with science; physics seems more feasible for integration with mathematics; CIMAS is perceived to increase student motivation and positive attitudes toward mathematics, to provide meaningful learning anda more effective teaching environment for school teachers. Although CIMAS is not seen to have disadvantages that hinder learning and teaching, the integration has limitations related to curriculum, teachers, and facilities that are obstacles to effective implementation. The main conclusions drawn from this study were that the integration of mathematics and science curriculum is expected to provide advantages and satisfy the psychological, pedagogical, and sociological needs of students. The findings could be valuable for curriculum developers, teachers, and teacher educators.