This paper provides a developmental perspective on the concept of source text (ST) influence in translation. ST influence is regarded as any influence a ST may have on the production of a target text (TT); as positive transfer, in which case the similarities between working languages are exploited in translation, and as negative transfer, in which case ST-induced solutions violate the TL norms or conventions. It is argued that translation is balancing between interlingual differences and similarities, avoiding the negative transfer that may result from the first while benefiting from the similarities. The emphasis in this paper is in student translation: it introduces results from a longitudinal study, focusing on the way a ST influences student translation at the beginning and end of BA level translator training. In the end, the implications of the study for translator training are discussed.