CEBS has published a position paper on counter cyclical capital buffers. It gives suggested guidance to supervisors under Level 2, which allows them to be flexible. The paper looks mainly at cyclicality of credit risk in the banking book of IRB banks. It focuses on the differences between the probabilities of default estimated by banks in an economic downturn and probabilities of default they currently apply. It gives options of calculating the buffer at portfolio level or at rating-grade level. CEBS hopes the document will help discussions rather than being a final answer.