The Revenue Department: How the Sales and Marketing Teams should work in order to achieve the set KPIs and ROIs

The Sales Department is supposed to sell, whilst the Marketing Department is to market the brand. It has been tradition for the two departments to lock horns and butt heads; the end result is a wastage of effort. 

Why not combine both into 'The Revenue Department', where the over-arching objective is to generate revenue? If the generation of revenue is owned by the new department, and it is given the empowerment to implement the necessary means to achieve it, then it is only logical for the endeavour to actually work. The department has no choice but to make it work.