A fractional role is when an experienced operator works with a company part-time and ongoing — usually one or two days a week, sometimes ten hours a month — instead of joining as a full-time hire. The company gets the strategic brain (CMO, COO, CTO, principal engineer) without carrying the salary, the benefits, and the org-chart fallout that a full-time senior hire brings.
I mostly meet fractional roles from the buyer side: a mid-sized business has hit a ceiling on something specific (SEO, WordPress architecture, delivery process) and needs senior help, but doesn't have a year of work to justify a hire. They want the judgement, not the headcount.
For the practitioner, the model trades single-employer security for a portfolio of clients. Lose one and the others keep the lights on. The trade-off is real: less benefits scaffolding, more business-development work, and a constant requirement to be useful in measurable ways. It's not for everyone, but for senior people who'd rather solve five interesting problems than be embedded in one company's politics, it's a sustainable shape.