PMP (Project Management Professional)
PMI's flagship. Requires 3+ years experience leading projects + 35 hours of formal PM education + a tough situational exam. Highest signal value in regulated / enterprise / government / construction environments. Less weighted in software-only careers.
CSM (Certified ScrumMaster)
Scrum Alliance, entry-level. Requires a 2-day in-person (or virtual) class + a relatively easy multiple-choice exam. Renewal every 2 years with continuing education + a fee. Useful for early-career signaling; less weighted at senior levels.
PSM (Professional Scrum Master)
Scrum.org, three levels (PSM I / II / III). No mandatory class. Harder exam — known for testing actual Scrum understanding, not memorization. No renewal fee. Free to take the assessment if you can pass it. Some hiring managers weight PSM higher than CSM for this reason.
PMI-ACP
PMI's agile cert. Covers Scrum, Kanban, Lean, XP, and others. Useful if you want PMI's brand on your agile knowledge — particularly relevant in orgs running hybrid models that already respect PMI.
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