In this article, Derek Francis looks at the process of assignment, whereby a tenant can sell, or 'assign', an existing leasehold interest to a new tenant. Most leases permit assignment on the condition that the landlord's consent to the assignment is obtained. In such circumstances, a landlord is duty-bound to consent to a tenant's proposed assignment unless it is reasonable for the landlord to withhold such consent. This article was first published in Scots Law Times, Issue 28 (published August 2013) and is reproduced here with kind permission of W Green, The Law Publishers.