The "Companion to Upstream Beginner A1+" is specially designed to enrich and enlarge student's vocabulary, focusing on the use of words in their everyday context. It functions both as a dictionary and as a supplementary practice book, thanks to its comprehensive lexical exercises.

The book consists of:
- about 1000 vocabulary entries, with all the new words and phrases from the coursebook explained in detail and labeled according to parts of speech
- pronunciation quide to all vocabulary entries
- definitions of the words in Greek
- lexical exercises practicing all essential vocabulary and grammar structures
- glossary for "Upstream Beginner Workbook"