There is daily ferry service between Lahaina on Maui, and Manele Bay on Lanai, with Expeditions Lanai Ferry. The 9-mile crossing costs $60 round-trip and takes about 45 minutes or so, depending on ocean conditions (which can make this trip a rough one).
Molokai Ferry offers twice-daily ferry service between Lahaina on Maui, and Kaunakakai on Molokai. Travel time is about 90 minutes each way, and the one-way fare is $71.51. Reservations are recommended.
Expeditions Lanai Ferry (800/695–2624. www.go-lanai.com.)
Molokai Ferry (877/500–6284. www.molokaiferry.com.)