Studies of minority and under-documented languages often present such languages as largely homogenous and pay relatively little attention to variation. Language descriptions may list names of dialects and often give a few cursory notes about the characteristics of such dialects, but descriptions rarely go into significant detail regarding observed dialect variation. This paper presents a case study of dialect variation in Bena, a minority language spoken in Tanzania. Data presented here was collected during a sociolinguistic survey of the Bena-speaking area, which found considerable phonetic, tonal, and lexical variation. The complexity of the data makes it impossible to draw distinct dialect areas which are clearly differentiated from one another. There are a number of different factors which contribute to the variation, including the existence of two different prestige varieties, language and dialect contact, and the influence of the national language, Swahili.