Service level agreements

When you buy a product, if it is mass produced you will be able to inspect it and perhaps try it out to see if it suits (think of buying a car). If the product is being made specially for you then you will have carefully specified it in terms of size, design and performance (think of contracting with a builder to construct an extension).

Services cannot be inspected in advance and they are often unique to each buyer (think of contracting with a cleaning company to clean your offices). A service level agreement is how you specify what the service provider must to under the contract eg for cleaning:

When?
How many people on cleaning team?
How long they spend?
What do they clean and how often?
What cleaning products?
How clean must the result be? (Cleaning an office would be to a different level compared to cleaning an operating theatre in a hospital.)

So the service level agreement attempts to define exactly what service will be provided.