The pair will take over from Jon Pratt who defected to Merrill Lynch earlier this month.
Joo will be based in Hong Kong, while Tan will be based in Singapore. Both will report to Vikram Malhotra, who heads Credit SuisseÆs global markets solutions group in Asia.
Joo will be responsibile of looking after Credit SuisseÆs high-grade and sovereign business. TanÆs focus will be the bankÆs high-yield business.