A 90‑Day Blueprint to Implement
HCM + AI

Spreadsheets don’t break during planning. They break when payroll is due, a start date shifts, and nobody can tell which file is “real.” That’s when you learn the problem isn’t data entry—it’s control.

Spreadsheets are fine for modeling. They fall apart as a system of record because people ops needs permissions, audit trails, and one source of truth. Even at scale, a surprising number of teams still use spreadsheets somewhere in the payroll workflow.

Why it breaks at scale

Around ~25–50 employees, “one spreadsheet” becomes a spreadsheet network: headcount, pay, time off, hiring, and org structure split across owners. Updates become invisible decisions, and every leadership question turns into reconciliation.

What most HCM + AI implementations get wrong

They start tool‑first, migrate messy data, and automate before workflows are clear. Then they expect AI to provide judgment. AI can accelerate admin; it can’t own accountability.

The 90‑day blueprint
(Build → Run → Scale)

Days 1–30: Build. Choose the system of record and appoint one internal owner with authority to set scope and say no. Clean the minimum viable dataset (who, role, manager, location, employment type, pay fields) and freeze legacy trackers to read‑only.

Days 31–60: Run. Treat payroll like a production migration. If anything material changes, run a parallel payroll and reconcile employee‑by‑employee. Integrate only what removes weekly manual work—because integration debt becomes a real weekly cost.

Days 61–90: Scale. Build leader‑grade visibility (org chart, headcount by function, planned vs. actual hires, cost rollups) and make managers approve changes in‑system. Add AI only where outputs are reversible: drafting, summarizing, and validations.

What good looks like after 90 days

Leadership gets reliable answers fast. Payroll runs without heroics. Changes flow through a clear approver path, with a clean record of what changed and when.

We build the systems behind great people.

People Street implements or stabilizes your HRIS, then runs managed People Ops with a documented cadence—so payroll, benefits, onboarding, and reporting stay clean as you grow. Book a consult or take the 3‑minute People Health Assessment. Not a PEO. Not unlimited admin. Not legal counsel.