# Founder of Trimarc, author of ADSecurity.org

Source: https://startwithidentity.com/experts/sean-metcalf/
Last updated: 2026-09-20
License: content by Start with Identity. Cite the source URL.

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## Bio

Sean Metcalf holds the Microsoft Certified Master certification in Directory Services, founded the consultancy Trimarc, and has published Active Directory and Entra ID security research at ADSecurity.org for over a decade, alongside talks at Black Hat, DEF CON, BSides, and DerbyCon.

Profile built from public research, conference, and company records.

## Where their work shows up

ADSecurity.org is the closest thing the field has to a defender's manual for Active Directory: what attackers actually do, in order, and which configuration changes break each step. It is where the working guidance on tiered administration, privileged group hygiene, and delegation review was written down in a form an administrator could act on the same week. See the [ITDR guide](https://startwithidentity.com/guides/security/identity-threat-detection-response-guide/), [password spraying](https://startwithidentity.com/techniques/password-spraying/), and the [best ITDR for Active Directory](https://startwithidentity.com/rankings/best-itdr-for-active-directory/) ranking.