The relationship between the yield of a government security and a corporate security of the same maturity – generally, government debt is considered default free. This means that when you purchase a government security you can be assured that you receive your principal and interest payments. However, when it comes to a corporate bond, this might not always be the case. Corporates that have strong cash flows, good future visibility and are able to service their debt with ease usually have very low risk of defaults. However, at the other end of the spectrum there are corporates that have a high default risk ie. lending money to these corporates would be riskier than lending money to better rated corporates. This gives rise to yield spread which is nothing but the yields offered on a government security and a corporate security that are of the same maturity. The difference in yield is simply the compensation that investors demand for assuming higher risk. In the current environment, these spreads have been widening. While G-Sec yields have been falling, the yields on corporate debt have been increasing since the ability of corporates to repay their debt has been compromised due a complete lack of economic activity.