MONTPELIER — The authors of a new book about the environmental movement in Vermont will discuss it Tuesday evening at the Goddard Art Gallery in downtown Montpelier.

The authors, Elizabeth Courtney and Eric Zencey, will be there from 5 to 7:30 p.m. to talk about the book, the last 50 years of the environmental movement, what they learned in writing the book, and what Vermont’s experience may mean for the planet.

“Greening Vermont: The Search for a Sustainable State” explores how the arrival of the petroleum economy in the 1950s transformed the state, and the response of the environmental movement.

Courtney has been a landscape architect, the executive director of the Vermont Natural Resources Council and a member and chairwoman of Vermont’s Act 250 Environmental Board.

Zencey has held multiple fellowships, including a Guggenheim, and is the author of the best-seller “Panama.” He is a fellow at the Gund Institute for Ecological Economics and a board member of VNRC.

The Goddard Art Gallery is at 54 Main St., across the street from City Hall.