One common procedure for oral performance testing of Foreign Language in the Elementary School (FLES) learners is one-on-one interviewing wherein the interviewer asks questions and the child candidate responds to them. While existing research has focused primarily on outcomes elicited by such procedures, this study examines the processes involved. During the present interview test for Japanese FLES students, the interviewers were permitted to provide support but without specific advice on how interviewers should give support to the candidates? problematic responses. Under such circumstances, (a) there were apparent inconsistencies between and within interviewers in the way they dealt with erroneous responses, and (b) the child candidates were not able to initiate the negotiation of meaning or repair processes. This study also suggests that, when interviewer support is taken into account in ratings of oral performances, such ratings may be significantly higher than ratings without interviewer support that are determined simply by the frequencies of correct responses to initial prompts and correctly formulated questions.