With her warm, truth-telling voice and her 60s-era Gibson Hummingbird guitar, singer-songwriter Jemima James is a cornerstone of the Vineyard folk-music scene. What’s new is her collaboration with (retired) West Tisbury Poet Laureate Dan Waters, who has recently taken to writing and performing his own Brazilian-inflected songs, or “guitar poems.” Jemima and Dan will perform together for the first time this Friday, April 9, at 7 pm at the Unitarian-Universalist Church on Main Street in Vineyard Haven. Suggested donation: $8. For information, call 508-696-0380.