An executive level meeting should to be established with your vendor.
Items to be discussed at this meeting are status of the relationship, executive level view of progress on work and strategy for both parties.
Invitees will be those who have strategic responsibilities within your business and your vendor organisation and will usually be your General Managers and Chief Officers (CIO, CFO etc.).
For your strategic vendors you should meet once a quarter.
Establishing an executive level meetings adds that additional layer to your relationship and helps executive levels to understand the concerns and strategic directions of the other company.