Lateral integration for law firms that want better partner outcomes

Law firms spend millions on lateral partner moves, yet too many still fail to deliver the expected return. The issue is rarely the hire alone; it is what happens after the offer is accepted.

That gap persists because integration is often treated as a separate coaching exercise, sitting between recruitment and L&D with no clear owner. By the time the partner arrives, the firm may already be reacting instead of planning.

Charles Currier, Senior Partner and Chairman of the Board for CMS UK and its international offices, brings a large-firm perspective shaped by a network of more than 22 member firms, around 10,000 people, and over 7,000 lawyers.

This article explains how lateral integration works when it is built into recruitment, due diligence and early business planning, and why that approach gives firms a better chance of helping laterals settle, perform and stay longer.

https://youtu.be/HrPOGcAXk7w

How lateral integration starts before the contract is signed

At CMS, the move begins before the contract is signed. The firm looks at strategy, client relationships and skills gaps first, then decides whether a lateral partner fits the plan.

That approach treats the hire as a business case, not just a resourcing decision. It also means the first steps of support, introductions and success measures are already being shaped before arrival.

Strategy first, opportunity second

The firm starts by asking where it has gaps in client relationships, sector coverage or capability. That reduces the risk of hiring because a name is available rather than because the role fits the strategy.

For law firms, that means the move should answer a real business need. If the need is unclear, the integration plan is usually unclear too.

Two way due diligence

CMS uses a broad due diligence process so both sides can learn about each other. The candidate meets people they would likely work with, while the firm gathers views from leadership, management and future colleagues.

That wider process helps surface concerns early and gives the candidate a clearer picture of the culture, structure and expectations that will shape the move.

Defining success before day one

The business plan includes practical questions such as what the first 100 days should look like and what success should look like after year one. That is a stronger starting point than assuming the lateral will work it out alone.

For lateral integration to work, the firm and the partner need the same definition of progress. Without that, the move can look successful on paper while failing in practice.

Why ownership matters

For Top 100 law firms, the budget question is central. If integration is the last step of recruitment, not a standalone coaching add-on, the cost should sit with recruitment rather than L&D.

That framing changes accountability. It makes the move part of the hiring decision, the business case and the responsibility for success.

• Identify the strategic gap.

• Test fit through broad due diligence.

• Build the first 100 days into the business case.

• Define year one success before the hire starts.

• Assign ownership inside recruitment.

The strongest lateral integration plans begin before the contract is signed and treat the move as part of recruitment, not an afterthought.

How the first 18 months shape partner performance

The early months after arrival are where many lateral moves lose momentum. CMS treats that period as a structured integration phase, not a vague settling-in period.

The aim is to shorten the time it takes for a new partner to deliver on the investment and to make the transition less frustrating for everyone involved.

A practical business plan

CMS uses a three year business plan with a heavy practical integration element. The plan covers internal introductions, client meetings and the steps needed to build traction.

For firms improving lateral integration, this is where the plan becomes operational. The partner should know who they need to meet, what support they will receive and how progress will be reviewed.

The role of the sponsoring partner

The sponsoring partner is not judged through a formal KPI, but the firm does track how the business plan develops over year one, year two and year three.

That creates a clear link between sponsorship and outcomes. If the hire is not progressing, the firm can ask whether the introductions, support and follow-through were strong enough.

Why welcome matters

New lateral partners often report feeling welcomed, with doors opened and commitments followed through. That feedback shows the firm has moved beyond process and into lived experience.

A safe, well-supported start matters because laterals are often leaving successful practices behind. They need confidence that the new platform will help them build, not just observe.

What firms should monitor

A useful review should look at whether the plan was followed, whether the right people were introduced and whether the business case still makes sense after the first year.

If patterns emerge in one department or practice area, the firm can learn from them rather than treating each move as a one-off event.

• Review points:

  • First 100 days

  • Year one business plan

  • Year two progress against expectations

  • Year three retention and growth

  • Department-level pattern review

The first 18 months should be managed against a plan, with visible support and regular review rather than informal hope.

How CMS's structure and culture affect integration

CMS is a large network with more than 22 member firms, around 10,000 people and over 7,000 lawyers. In that kind of organisation, integration depends on more than one sponsor or one team.

The firm describes itself as a single firm in the ways that matter to clients, even though it has separate profit pools behind the scenes. That makes collaboration and follow-through especially important for laterals.

One firm for the client

CMS says clients receive a single engagement letter, joined up teams and one bill, even though the profit structure sits across separate pools. That means integration has to work across offices and practice groups, not just inside one team.

For a lateral partner, this matters because the move is really into a platform. The firm has to make that platform visible, usable and coherent from the start.

Culture as an operating mechanism

Currier described the culture as taking work seriously without taking people too seriously. He also stressed respect, openness and being decent to people.

That is not soft language in a large partnership. It shapes how people share work, open doors and make a lateral feel that the move is real rather than symbolic.

Why structure affects collaboration

A non financially integrated model can create extra pressure on collaboration and cross selling. That means integration has to be supported by active internal behaviour, not just by a welcome pack.

CMS addresses this by investing in shared tools and global agreements, including enterprise technology arrangements. The point is to make collaboration easier once the lateral arrives.

What Top 100 firms should notice

For Top 100 law firms, the lesson is direct. If integration falls between recruitment and L&D, the lateral may never get the joined up support needed to succeed.

Ownership matters as much as coaching. Lateral integration works best when recruitment, leadership and the sponsoring partner all treat it as part of the hire itself.

• Culture and structure checklist:

  • Can the lateral see how the firm really works?

  • Are internal introductions planned across offices?

  • Is collaboration supported by systems and incentives?

  • Does the firm present one joined up platform to clients?

  • Is integration owned by recruitment?

In a large firm, integration succeeds when culture, structure and client delivery all point in the same direction.

How firms reduce risk and improve retention

Not every lateral move works out, and no due diligence process can remove every risk. The point is to reduce avoidable failure and learn faster when a move does not deliver as expected.

CMS reviews performance against the original business plan and looks for patterns across departments, which helps the firm improve future hires rather than repeating the same mistakes.

Why some laterals succeed and others do not

Currier pointed to luck, limited due diligence and unmet expectations around client transfer as factors that can affect outcomes. Even strong candidates can struggle if the expected work does not materialise.

That is why integration needs realistic assumptions. A firm should not assume that a successful track record elsewhere will automatically translate into success on a new platform.

Learning from exits as well as successes

Some laterals leave after a few years because they have done well and are ready for the next step. Others leave because the move did not deliver what both sides hoped for.

Either way, the firm can review what happened. That review is valuable because it shows whether the integration plan, the client expectations or the internal support need to change.

The safe space problem

Laterals also need a safe space to talk about fears, concerns and the pressure of starting again in a new firm. If those concerns stay hidden, the firm may only see the problem after momentum has already been lost.

A structured integration programme gives those issues a place to surface early. That is especially useful when the hire is expensive and the expectations are high.

A practical retention lens

Retention improves when the firm knows what it is trying to achieve, who owns the move and how progress will be measured. That is especially true where the hire is expensive and the expectations are high.

For firms that want better returns from lateral integration, the question is not whether every move will succeed. It is whether the firm is giving each move the best possible chance.

• Risk reduction checklist:

  • Test fit on both sides

  • Confirm client and market assumptions

  • Build in early support

  • Review year one and year two outcomes

  • Capture lessons from exits

Integration lowers risk when firms review outcomes honestly and use each move to improve the next one.

Conclusion

Lateral integration works best when it is treated as the final stage of recruitment, not a separate coaching project. That shift changes ownership, budget and accountability, which is exactly where many law firms need clarity.

For firms that spend heavily on lateral partner moves, the practical question is simple: are they building the integration plan before the hire starts, or after the problems appear? The firms that answer that well are more likely to help laterals perform, stay and grow.

If the goal is better retention and stronger returns, lateral integration should be planned, measured and owned from the start.

FAQs

What is lateral integration in a law firm?

Lateral integration is the process of helping a partner or team settle into a new firm and start performing quickly. It includes business planning, introductions, cultural fit and early support, not just onboarding paperwork.

Why does lateral integration fail so often?

It often fails when firms treat the move as a recruitment win rather than a business transition. Weak due diligence, unclear success measures and poor follow-through can leave the new partner without the support needed to deliver.

Should lateral integration sit in recruitment or L&D?

For many firms, it makes more sense to treat lateral integration as the last step of recruitment. That keeps ownership with the people making the hire and avoids the common gap between recruitment and L&D.

How long does lateral integration usually take?

The article notes that many lateral hires take about 18 months or more to deliver on the investment. Firms can shorten that by building the first 100 days and year one plan into the hire from the start.

What should a firm measure after a lateral hire joins?

A firm should compare the original business plan with year one, year two and year three progress. It should also look for patterns across departments so it can improve future lateral integration decisions.