Paul's letter to Titus, together with 1 and 2 Timothy, form what are commonly called the Pastoral Epistles.
First called "Pastoral" in the eighteenth century, they were given this label because they emphasise pasturing responsibilities.
However, it might be more accurate to call them Leadership Epistles, because leadership is addressed here on many fronts: personal, parental, spousal, generational, pastoral, evangelistic and apostolic.