Richard Piper has been appointed as chief executive of Alcohol Research UK. Piper, who is a former chief executive of Roald Dahl’s Marvellous Children’s Charity, will join in September from the learning disability charity Mencap, where he is director of impact transformation.

Dame Helen Ghosh is to step down in March as director general of the National Trust to become master of Balliol College, Oxford. She has led the charity since 2012.

The Anglican mission agency USPG has appointed Rev Duncan Dormor as its next chief executive. Dormor, who is dean of St John’s College, Cambridge, succeeds Janette O’Neill, who is retiring after six years in the post.

Janet Vitmayer, chief executive of the Horniman Museum and Gardens, is to retire in March after 20 years in the role.

The Lake District Foundation, a new charity that is being set up to continue and build on the work of the tourism and conservation charity Nurture Lakeland, has appointed Sarah Swindley as its first chief executive. She was chief executive of Lancashire Women’s Centres.

John Christensen, founding chief executive of the Great Western Air Ambulance Charity, has announced that he will retire at the end of the month after nine years in the role.