On their website, the HLC identifies five criteria, each divided into core components, that University must provide evidence they meet in order to be accredited.
For more information, please see the HLC website.
The five main areas are:
Criterion One: Mission
Criterion Two: Integrity: Ethical and Responsible Conduct
Criterion Three: Teaching and Learning: Quality, Resources, and Support
Criterion Four: Teaching and Learning: Evaluation and Improvement
Criterion Five: Resources, Planning, and Institutional Effectiveness