The 10 top M&A deal rainmakers of the 21st century

Mergers and acquisitions (M&A) might sound like a sterile world of spreadsheets, lawyers, and late-night conference calls—but behind every headline-grabbing deal is a human story. Deals don’t just “happen”; they’re engineered, negotiated, and sometimes willed into existence by a rare breed of professionals known as rainmakers. These are the people who can pick up the phone and make CEOs listen, who can turn a “maybe” into a multi-billion-dollar “yes,” and who know how to navigate the minefield of valuation, regulation, and egos without blowing up the deal.

In this article, we’ll unpack what makes a rainmaker so critical to the M&A process, why the right person can mean the difference between a good outcome and a great one, and then spotlight 10 of the most influential dealmakers of the 21st century. Whether you’re a curious newcomer or a seasoned pro, you’ll find insights, war stories, and even a visual framework to understand the skill sets that separate the good from the legendary. Buckle up—because in the world of M&A, when it rains, it pours.

1) Bruce Wasserstein — the archetype who re‑wrote the M&A playbook for a new century

• Who/where: Former Chairman & CEO of Lazard (2005–2009); previously co‑founded Wasserstein Perella. Passed away in 2009. 
• Why he matters: Even though his legend began in the 1980s, Wasserstein’s influence persisted into the 2000s as he restored Lazard to the top table and institutionalized a style of tactical, high‑stakes M&A that many boutiques emulate today. He was renowned for out‑maneuvering rivals and pushing clients to “dare to be great.” 
• Major deals (career highlights): RJR Nabisco (1988), Texaco–Getty, Philip Morris–Kraft (1988), and numerous boardroom battles that shaped modern takeover defense—all part of the lineage that informed 21st‑century activism and contested bids. 
• Specialty: Hostile/contested M&A, corporate strategy at scale, board‑level counsel. 
• Status: Deceased (2009); legacy continues to define “rainmaker” culture. 

2) Ken Moelis — architect of the modern independent advisory firm

• Who/where: Founder, Chairman & CEO, Moelis & Company (since 2007); previously President of UBS Investment Bank. 
• Why he matters: Moelis helped usher in the post‑crisis rise of elite boutiques by pairing senior‑only coverage with conflict‑free advice. Before launching his firm, he rebuilt UBS’s U.S. banking franchise; afterward, he proved a boutique could win and execute mega‑deals and complex restructurings globally. 
• Major deals: Early Moelis mandates included Anheuser‑Busch’s sale to InBev ($61B), Hilton’s sale to Blackstone ($26.5B), Yahoo’s defense against Microsoft’s unsolicited bid ($44.6B), and the Dubai World/Nakheel restructurings (~$49B liabilities across entities; $24.9B formal Dubai World restructuring). 
• Specialty: Cross‑border M&A and large‑scale restructurings; building senior teams that win. 
• Status: Active as founder–CEO (with a public firm behind him). 

3) Paul Taubman — the solo act who built a public advisory powerhouse

• Who/where: Founder, Chairman & CEO, PJT Partners (formed via Blackstone’s corporate finance spin and Taubman’s boutique); ex‑Morgan Stanley co‑president. 
• Why he matters: After leaving Morgan Stanley, Taubman immediately landed Verizon as a client for the $130 billion acquisition of Vodafone’s 45% of Verizon Wireless—one of history’s largest cash‑heavy deals—proving that a single trusted adviser can sit at the core of titanic transactions. He then scaled PJT into a public firm spanning M&A, restructuring, and fundraising. 
• Major deals: Verizon–Vodafone (Verizon Wireless buy‑in, $130B); a string of mega‑mandates thereafter as PJT climbed league tables (per Dealogic/press). 
• Specialty: Telecom, C‑suite counsel, and complex separations/recombinations. 
• Status: Active as PJT’s chair & CEO. 

4) Michael Klein — sovereign relationships meet mega‑deals

• Who/where: Founder, M. Klein & Company; former Citigroup rainmaker; designated (in 2023) to lead the carved‑out CS First Boston before UBS’s acquisition of Credit Suisse altered that plan. 
• Why he matters: Klein blends blue‑chip corporate M&A pedigree with sovereign ties—especially in Saudi Arabia—that open doors on transactions and capital markets. He was a senior adviser around the Saudi Aramco IPO, the world’s largest by proceeds, and has been instrumental in Middle East deal flow and bank restructuring moves. 
• Major deals: Advisory roles around Aramco’s ~$25–26B IPO (2019) and strategic work with Saudi entities; earlier, heavyweight mandates at Citi across energy and consumer (e.g., Gillette–P&G, Chevron–Texaco—he was a Citi leader across that era). 
• Specialty: Sovereign and Middle East capital/transactions; energy; complex carve‑outs. 
• Status: Active at M. Klein & Co.; high‑level adviser. 

5) Blair Effron — the consigliere behind many of the decade’s defining consumer & media deals

• Who/where: Co‑founder & Partner, Centerview Partners. 
• Why he matters: Effron is the quintessential boardroom counselor—trusted by blue‑chip CEOs across consumer, retail, healthcare, and TMT. Centerview’s model (few clients, deep relationships, heavy partner time) has produced a run of era‑defining transactions with repeat clients. 
• Major deals: Disney’s $71.3B acquisition of 21st Century Fox assets; Tiffany’s $16B+ sale to LVMH; Heinz–Kraft combination; Time Warner Cable’s $79B deal with Charter; Sprint–T‑Mobile; GE Oil & Gas–Baker Hughes; and more. 
• Specialty: TMT + consumer/retail + healthcare; activist defense and complex spin/merge pathways. 
• Status: Active partner at Centerview. 

6) Frank Quattrone — the enduring sage of Silicon Valley dealmaking

• Who/where: Founder & Executive Chairman, Qatalyst Partners. 
• Why he matters: For four decades, Quattrone has been in the room for technology’s biggest capital markets and M&A moments—from IPOs (Amazon, Cisco, Netscape back in the day) to the most strategic sell‑sides of the cloud era. His imprimatur on a tech process signals to buyers: this will be competitive. 
• Major deals: LinkedIn’s $28.1B sale to Microsoft, Motorola Mobility’s $12.5B sale to Google, 3PAR’s auction to HP, Twitch’s $1B sale to Amazon, Ansys’s pending ~$34.8B sale to Synopsys (advisory role), among many others. 
• Specialty: Technology M&A, especially seller processes and premium price discovery. 
• Status: Active as Executive Chairman at Qatalyst. 

7) Aryeh Bourkoff — media’s modern power broker

• Who/where: Founder & CEO, LionTree. 
• Why he matters: In TMT, relationships are king—and Bourkoff has built the go‑to boutique for Hollywood, telecoms, and digital platforms. He’s been central to the industry’s biggest recombinations and divestitures of the 2010s–2020s, often sitting between old media, streamers, and telecom balance sheets. 
• Major deals: AT&T’s separation of WarnerMedia and its merger with Discovery; Amazon’s $8.45B acquisition of MGM; Apollo’s ~$5B acquisition of Yahoo from Verizon; prior work on Virgin Media sale to Liberty Global, Verizon–AOL, Charter–Time Warner Cable, etc. 
• Specialty: TMT convergence, streaming, digital commerce; cross‑owner diplomacy. 
• Status: Active CEO at LionTree. 

8) Byron Trott — the discreet consigliere to founders and families (and Buffett)

• Who/where: Co‑CEO & Chairman, BDT & MSD Partners (formed 2023 by combining BDT & Co. with MSD Partners); ex‑Goldman Vice Chair of IB. 
• Why he matters: Trott re‑popularized the merchant bank to the closely held model—advising and investing alongside founder‑ and family‑led companies at generational inflection points. His long association with Warren Buffett underscores the trust he commands in sensitive situations. 
• Major deals: Brought Berkshire into Mars–Wrigley ($23B), including billions in Berkshire financing; advised on Pritzker’s Marmon sale to Berkshire ($4.5B); and helped secure Berkshire’s $5B capital infusion into Goldman during the 2008 crisis—plus scores of founder/family transactions thereafter. 
• Specialty: Founder/family capital and governance; long‑term partnerships; consumer and industrials. 
• Status: Active as co‑CEO of BDT & MSD. 

9) Sir Simon Robey — the quiet British force behind U.K. megadeals

• Who/where: Co‑founder, Robey Warshaw; ex‑Morgan Stanley co‑chair of global M&A. 
• Why he matters: Robey Warshaw is tiny by headcount but gargantuan in influence across FTSE boardrooms. The firm’s fingerprints are on the U.K.’s biggest strategic moments, often advising “national champions” and global buyers alike. 
• Major deals: Comcast’s ~$39–40B acquisition of Sky (where Robey Warshaw helped deliver the knockout bid), advisory work for LSE on its $27B acquisition of Refinitiv (and defense vs HKEX), and recent work around Vodafone–Three UK (a transformational wireless merger). 
• Specialty: Board‑level counsel, contested U.K. transactions, and “small team, big mandate” execution. 
• Status: Active partner at Robey Warshaw. 

10) Anu Aiyengar — the bulge‑bracket leader redefining the role at scale

• Who/where: Global Head of Advisory and M&A, J.P. Morgan. 
• Why she matters: Aiyengar is the most senior M&A executive at the world’s largest bank by market cap—a rare and influential seat. Her transaction sheet spans LVMH–Tiffany, E*TRADE–Morgan Stanley, Navistar–TRATON, Siemens Healthineers–Varian, Allergan–AbbVie and more, and she’s a prominent voice on the future of mega‑deals and cross‑border consolidation. 
• Major deals: LVMH’s acquisition of Tiffany, E*TRADE’s sale to Morgan Stanley, Siemens Healthineers–Varian, Allergan’s sale to AbbVie, among many others across sectors and geographies. 
• Specialty: Large‑cap, cross‑border M&A across consumer, healthcare, industrials, and TMT; senior‑level board counsel at scale. 
• Status: Active, overseeing JPM’s global advisory franchise. 

Honorable mentions (because the 2000s–2020s were rich with talent)

• Simon Warshaw (Robey Warshaw co‑founder; ex‑UBS). His role on the $130B Vodafone–Verizon Wireless transaction cemented his status before he co‑founded RW. 
• George Boutros (Qatalyst CEO). A formidable closer on tech’s biggest sell‑sides—from LinkedIn–Microsoft to Slack–Salesforce and Figma–Adobe (pending/subject to regulatory outcomes at various points). 
• Yoël & Michael Zaoui (Zaoui & Co.). Boutique advisers behind marquee European moves like GSK/Novartis asset swap and Nokia’s acquisition of Alcatel‑Lucent. 

How to “hire” a rainmaker mindset (even if your budget can’t)

1. Define what you’re optimizing for (speed, certainty, regulatory solvability, seller premium), then pick the type of rainmaker accordingly (see the radar chart). 
2. Demand senior time and a real plan (bidder map, regulatory pathway, messaging for both boards). 
3. Coach your own side—set rules of engagement, align on trade‑offs, and deputize a decision‑making core to match the other side’s pace. 
4. Remember the counterparty is reading the signals: who you hire is itself a negotiating message. 

Conclusion: The forecast calls for rain (if you pick the right clouds)

When boards grumble that “multiples are multiples,” remember that markets are social and structural. A great rainmaker won’t guarantee sunshine—but they’ll expand your buyer set, sharpen your story, tilt negotiation gravity, and build a regulatory runway you can actually land on. That’s how you get both the right price and the right counterparty in the 21st century. Which type of rainmaker do you think creates the most value in today’s antitrust‑heavy, geopolitically noisy deal world—and why? Share a war story (or a cautionary tale) in the comments.