A measure of the quality of a borrower as perceived by the market. It varies over different maturities and for different interest rate instruments (like fixed for floating interest rate swaps). For example, a good credit entity (AAA rated) can borrow for six months at a floating rate benchmark, such as LIBOR, less 30 basis points and for five years at a fixed rate of 8.5%. In contrast, a poor credit firm (A rated) can borrow for six months at LIBOR plus 70 basis points and for five years at a fixed rate of 10.5%. It follows that the quality spread in the five year market is 10.5%- 8.5% = 2% or 200 basis points. Likewise, it is in the LIBOR market: (LIBOR+ 70) – (LIBOR- 30)= 100 basis points or 1%.