One avenue for developing second language (L2) vocabulary knowledge is through Extensive Reading (ER). ER can provide opportunities for incidental learning to occur. Class time is often too restricted for sufficient attention to deliberate learning (Hunt & Beglar, 2005) meaning ER is important for L2 vocabulary development. This article builds on ideas in the recent two-part "Reading in a Foreign Language" ER discussion forum by investigating two implementations of ER and their effects on L2 vocabulary development: a traditional ER-only approach, and an ER-plus approach which supplements ER with post-reading discussion implemented in small groups. L2 English learners enrolled at a university in Aotearoa New Zealand read five graded readers during normal class time. Latent Semantic Analysis was used to measure the development of word association knowledge of 60 target words. The findings revealed facilitative effects of both ER approaches. Supplementing ER with discussion provided opportunities for further development.