The present study examined the effects of different types of written input on the learning and retention of collocational knowledge. Eighty-three second language (L2) learners from four intact classes were divided into a control group and three treatment groups. The treatment groups were provided with infrequent grammatical collocations embedded in genuine input, elaborated input, and modified elaborated input. They were exposed to the collocations during five instructional sessions and were assessed on their receptive and productive collocation knowledge using immediate and delayed posttests. The results indicated that (a) receptive and productive collocation knowledge can be learned incidentally through multiple exposures in genuine, elaborated, and modified elaborated input and (b) modified elaborated input, which induces more focus on form (FonF), can lead to significant immediate and long-term gains in receptive collocation knowledge.