We asked 3 CAS leaders what's changing in their practices. Here's what they told us.

CPA.com has co-hosted BILL's Accountants Partner Council for close to a decade. It's where the profession directly shapes how BILL's product evolves, and where firm leaders compare notes on how people, process and technology are moving as the work itself changes under AI operating models.

This year's State of the Profession panel got specific. I had a discussion with three firm leaders who run practices at very different scales, in very different markets. We spent an hour comparing what's changing inside their CAS practices right now.

Here are the five most important themes from our conversation.

Everyone underestimates change management

You can't bolt advisory onto a compliance structure and expect it to scale. Firms try it anyway, and when that approach falls short, the disconnect comes down to announcing a change and leaving the operating model untouched underneath it.

"There's this perception that you just flip the switch, you say you're changing something, and if people aren't doing it, it must be a communication problem. But really, it's the operating model. It's how we do it. It's what we do day to day." That's panelist Missy Thompson of Baker Tilly, a top 10 firm currently integrating last year's Moss Adams merger, commenting on the gap she sees between announcing change and actually building it into daily work. Clear communication is a good start. But if the incentives and daily workflow still reward the old behavior, nothing actually changes.

Growth by design beats growth by accident

The firms furthest along with their CAS practice growth aren't chasing every prospect that walks in. They've built guardrails (such as clearly defined client criteria and a willingness to say no) and treat that discipline as a growth strategy, not a limitation.

"We turn clients away all the time," Mairtini Ni Dhomhnaill told us. She’s the founder of Countsy, an organization that provides accounting and HR services exclusively to venture-backed startups and scale-ups, and treats the firm's willingness to refuse clients as a strategy rather than exception. Every client who's a poor fit costs more in delivery time and team morale than the one who never signs.

That same discipline applies to the lines of business a firm builds, not just which clients it takes. One firm on the panel described testing new industry verticals through an internal incubator and walking away from one, despite having real expertise in it elsewhere in the firm, once the numbers didn't support scaling it as a CAS offering. A strategic “no” isn't a limitation on growth. It's what makes growth sustainable.

AI only counts once it's embedded, not while it's being tested

The AI conversation among these firms has already moved past what they could build to what's actually embedded inside the workflow. One firm's approach is to automate the routine work first using BILL's own tools, then layer agentic tools on top of what's left. The goal: having a dedicated digital agent working alongside the team on every client account by year's end.

Another panelist shared that if you can pull AI back out of a process and the work still functions the same, it was never embedded to begin with. That's the difference between experimentation and operationalization, and most CAS practices are still on the experimentation side. Firms need to shift in the direction of operationalization.

Pricing hasn't caught up to the value being delivered

Clients aren't buying time anymore. They're buying clarity, confidence, and results. That shift is forcing a harder conversation than most firms expected. If AI cuts a ten-hour engagement down to one, the fixed fee built around ten hours doesn't hold. Neither does the instinct to just discount it.

Firms that have moved past experimentation are renegotiating what the fee actually covers and pointing clients toward the deeper insight that used to get squeezed out by large volumes of manual work. One outsourced accounting leader on the panel put the underlying shift bluntly: accounting departments are going away, but accounting isn't. The firms that operationalize this well stand to gain far more engagements than they lose in per-hour revenue.

The advisor of the future needs a different runway

Firms used to have six to ten years to develop someone into a true advisor. Now it's closer to two. That timeline doesn't work with the old apprenticeship model. Firms are rebuilding it using shorter, competency-based tracks, mentorship that's required rather than optional, and hiring for intellectual curiosity over technical polish (because they know the technical piece can still be taught).

Irfan Dossani, who leads the advisory practice at Whitley Penn, notes that studies have shown that the majority of on-the-job learning happens by watching someone else do the work, not from a video. With less time to let that happen organically, some firms are engineering it directly. For example, they're training new hires through live-fire simulations of difficult client conversations to help them build the judgment that used to take years to learn through job shadowing.

These five themes build on each other. Fix the operating model first, or growth stays accidental. Embed the AI first, or pricing remains guesswork. Skip either, and no amount of talent development makes up the difference.

That's the transformation CPA.com and BILL are built to support. Together, more than 9,000 firms already use CPA.com and BILL to handle integrated financial operations for their clients. Where do you start? Focus first on the theme where your firm has the greatest gap between where you are today and where you want to be. Learn more: CPA.com/BILL

About the author

Kim Blascoe, CPA, leads CPA.com's CAS practice transformation programs, focusing on helping firms establish and grow optimized CAS practices through consulting, practice development, and training offerings. Prior to joining CPA.com, Kim spent more than 30 years in public accounting, including leading the CAS practice for a Top 20 firm.