The purpose of this study was to examine whether licensed in-service teachers of English for speakers of other languages (ESOL) in K-12 schools are more knowledgeable in the area of applied linguistics than their nonlicensed counterparts, and whether the ESOL-licensed teachers who have taken courses toward their licensure are more knowledgeable in applied linguistics than their counterparts who have not taken any courses before being licensed. Data were collected from 201 PK-12 in-service teachers in Kansas. A chi-square statistical test was used to analyze the association between and among the above-mentioned variables. The results of this study suggest that teachers who are ESOL licensed and also those who have taken ESOL coursework are more knowledgeable in applied linguistics than teachers who are not ESOL licensed or those who have not taken any ESOL courses. (Contains 7 tables.)