“Night Has Fallen” is a call-and-response piece: the cantor sings a line which the people echo, and then everyone sings a refrain together. The tune, “Dzuwa Lapita”, is from Malawi, and was arranged and harmonized for publication in the UK/US by John Bell. The words in English are by Tom Colvin, but also you can make up your own calls and responses.
This song is available in the Iona Community's There Is One Among Us: Shorter Songs for Worship from Wild Goose Publications.
Here is a video of AnnaMarie Hoos leading 'Night has Fallen' at an MMC event at Bishop's Ranch in January 2016.