Flights to Kihnu and Ruhnu islands start from Pärnu airport and are operated by Avies. Schedules change by season and during the winter planes usually go only once a day, so booking your ticket in advance is important.
When the sea is not frozen, all of these islands have a regular boat connection through the Pärnu port. You need to check for schedules, as they may vary greatly during different seasons. Tickets cost up to 5EUR and Manilaid and Munalaid are a part of the Kihnu-Pärnu ferry route.
Boats are operated by Kihnu Veeteed.