The problem of second language acquisition and its true nature is a controversial issue in second language teaching. Different camps propose different methods to approach the very nature of second language acquisition. Among these, Stephen Krashen and his advocates raised the issue of implicit second language teaching and the prominence of input that are expounded in the present article. In so doing, some criticisms put forth by proponents of explicit second language teaching will be presented and answered briefly by Krashen in an interview.