This study examined teacher interns' and their classroom cooperating teachers' concerns about the extended practicum both before and after their completion of the 16-week program. Respondents completed pre- and post-internship surveys identifying their initial concerns about the internship and the subsequent alleviation of these concerns (or the emergence of others). All the respondents reported that some of their initial apprehensions were alleviated by the end of the internship, but nearly all also stated that some concerns remained and that some new concerns had emerged. The teacher interns all reported having developed specific professional strengths during the internship. Evidence supporting some of Fuller and Bown's (1975) three-stage concern theory was found. Implications of these findings are drawn for enhancing the effectiveness of extended practicum programs.