Customer call center authentication (CCCA) combines human and machine processes, tools, and technologies. The call center is invariably the channel of last resort for customers looking to get things done, but it’s still a largely analog avenue riddled with security holes. Improving CCCA security while reducing customer friction and improving customer and agent experiences is a core building block of a successful digital transformation. This report provides CCCA best practices to help security and risk (S&R) pros beef up customer call center security.