German to English Bus/Financial Education / Pedagogy Labour Relations

This isobviously a certification of studies and/or a personal reference but at present I can't think of the exact English equivalent!

It is issued by a company which provided xxx with on-the job training in retail sales, which she supplemented by night school classes. Noting "eine dreijährige Lehre als Detailhandelsangestelle" the document details the work areas and tasks covered, the personal qualities displayed by xxx, and conveys the company's thanks to her and good wishes for her future.