(22)Credit rating agencies should establish, maintain, enforce and document an effective internal control structure governing the implementation of policies and procedures for the prevention and control of possible conflicts of interest and for ensuring the independence of credit ratings, rating analysts and rating teams regarding shareholders, administrative and management bodies and sales and marketing activities. Standard Operating Procedures (SOPs) should be put in place relating to corporate governance, organisational matters, and the management of conflicts of interest. SOPs should be periodically reviewed and monitored to evaluate their effectiveness and whether they should be updated.