A mitre joint for a metallic frame of a fenestration unit includes first and second frame members; a connector configured to locate the first and second frame members in relation to one another; and first and second fasteners configured to secure the first and second frame members to the connector. The connector has a first arm configured to extend within a hollow profile defined by the first frame member, and a second arm configured to extend within a hollow profile defined by the second frame member. A longitudinal axis of each of the first and second fasteners is configured to be parallel to a longitudinal axis of the respective connector arm. Each of the first and second fasteners is configured to engage the respective frame member when the respective connector arm extends within said frame member.