Complex problems and concepts must be broken down into smaller problems in order to manage them. The Customer Experience Management Maturity Model, or CEM3 (based on the Capability Maturity Model), provides a framework for understanding and improving processes implemented to manage the customer experience.

I'll be expanding on this model over the course of several articles, but here's a high level description of each maturity level.
Initial
Customer experience is typically limited to static HTML or a basic web site describing products or services. Processes are ad-hoc. Success is dependent on the heroics of individuals.
Repeatable
Basic project and content management processes are put into place to make customer interactions repeatable. Customer experience workflows and processes are documented. Management has visibility into major milestone accomplishments and project status.
Repeatable customer experience processes may be limited to a single group within an organization, such as Marketing. Different processes may be implemented for different projects.
Defined
CEM processes are tailored from organization wide, cross-functional standards and processes. Standard processes are used to establish consistency across all customer touchpoints.
Managed
All interactions are measured within the customer life cycle. Dashboards are created to monitor CEM Key Performance Indicators (KPIs). Management can identify ways to adjust and adapt the process to particular projects without measurable losses of quality or deviations from specifications. Organizations at this level set quantitative goals for customer experiences.
Optimizing
Maturity level 5 focuses on continually improving process performance through both incremental and innovative technological improvements. Quantitative process-improvement objectives for the organization are established, continually revised to reflect changing business objectives, and used as criteria in managing process improvement.