Credentials, diplomas, degrees, certificates, licenses, badges, apprenticeship completions, and others such markers of achievement may be "stacked " or combined into clusters.  The most familiar form is stacked atop each other, as in earning a series of increasingly-difficult college degrees with diplomas.

Credentials may also be combined based on the value added to an industry or an employer.  For example, credentials in Occupational Safety & Health may be stacked into increasing levels of competence.

Credentials from the Soft Technical Skills Institute (STSI) for all 60 of the Soft Technical Skills from www.Lesson-up.net may be stacked into nearly-infinite patterns depending on need and opportunity.