The current study examines the role of instruction in developing L2 learners' ability to comprehend two types of implicatures: indirect refusals and indirect opinions. According to Taguchi (2005), these implicatures differ in the degrees of conventionality involved in producing them, hence requiring different degrees of processing effort on the learner's part. Our second aim, therefore, is to examine which implicature type is more teachable. Two upper-intermediate classes of EFL learners were randomly assigned to the control and treatment conditions. The treatment group received meta-pragmatic instruction on the target implicatures and inferencing strategies while the control group followed a regular syllabus. The learning outcomes were measured by means of two parallel pragmatic listening tests before and after the study. An interview with eight learners was also conducted at the end of the study to examine the learners' use of inferencing strategies. Results of the pragmatic listening tests suggested that while learners improved their comprehension of both types of implicatures, instruction produced a larger effect on indirect refusals. Findings from the interview also revealed more effective use of inferencing strategies by the learners after the treatment. The findings are discussed with implications for instruction in and research on pragmatic comprehension.