ZS Associates

ZS was founded in 1983[8] by Andris Zoltners, then the Frederic Esser Nemmers Distinguished Professor Emeritus of Marketing at the Kellogg School of Management, and Prabhakant (Prabha) Sinha, then an associate professor of marketing at the Kellogg School of Management. While at the University of Massachusetts, they conducted research together into the knapsack problem,[9] a combinatorial optimization problem that is used to determine the number of items that fit in a collection so that the total weight of those items together is less than or equal to a given limit. They realized that their research could be applied not only to planning and distributing meals for astronauts and members of U.S. military, but also to consumer industry issues related to sales force sizing and resource allocation.

In 1982, Zoltners and Sinha presented their sales force sizing and territory alignment models to their academic colleagues, demonstrating the world’s first personal-computer-aided territory mapping system.[10] In 1983, Sinha joined Zoltners at Northwestern, and the pair founded ZS Associates in their off hours, offering companies increased sales force efficiency using their now-proven territory mapping software. In its first three years, ZS had helped eight of the 10 largest pharmaceutical companies in the world, including Pfizer, align territories and resize their sales forces. By that time, the 25-member team worked on 100 or more projects in a dozen countries—including the United States, Canada and many European countries.

In 1987, a large American company hired ZS to reorganize, redesign and reallocate their US-based sales force. In addition to deploying their sales territory alignment solution, ZS also supported the company in change management, and built tools like incentive compensation programs to support the human resources of the company’s marketing and sales division.

Through the 1990s, ZS continued to develop its capabilities,[11] adding data warehousing, market forecasting, market research and analytical services for their clients. The firm also broke into sales force incentive compensation program auditing, design and implementation during these years.

In 2002, ZS added a marketing research practice to the company that would soon expand and evolve into a marketing solution area. 2004 saw Zoltners and Sinha win the Marketing Science Practice Prize from the Institute for Operations Research and the Management Sciences (INFORMS) for their paper, Sales Territory Design: 30 Years of Modeling and Implementation,[12] which explored the “models, systems, processes, and wisdom [that] have evolved over 1,500 project implementations for 500 companies with 500,000 sales territories.”

From 2003 to 2011, the firm tripled its revenue by expanding practice areas and solution areas from eight areas to 20, and by enlarging ZS’s focus from pharmaceutical sales force sizing and territory alignment to a business-to-business sales, marketing, operations and capability-building global business. In the same period, ZS went from 10 offices around the world to 19 offices, establishing its presence around the globe.[13]

In 2007, the company reached a headcount of 1,000 (with a majority of the staff holding advanced degrees in business and related disciplines) with 2,000 projects completed in a single year for 300 different clients in 28 industries and 38 different countries. The company marketed its consultants as “experts in our issue areas, not generalists.”

By 2011, ZS worked with 49 of the 50 largest drugmakers in healthcare and 17 of the 20 largest medical device makers.

ZS celebrated its 35th anniversary in 2018 with a 6,000-employee headcount and 22 offices around the world. That same year, Vault ranked ZS #7 on its list of 2018 Best Consulting Firms for Health Care Consulting.[14] ZS would go on to rank #6 on the same list in 2019.

ZS has been recognized with several award related to its work environment, its employees and its success in the consulting industry.

• Named one of Consulting magazine's 2017 [18] and 2018 [19] "Best Firms to Work For".
• Ranked by Vault on several 2019 best-of-list, including "Consulting 50", "Most prestigious Consulting firms[20]" and "Best consulting firms".
• Ranked by Forbes as among the top 25 companies which are the most difficult to interview for.[21]