Great beaches, a famous theater and fine schools are just some of the traits giving Westport its outward charm. But look a little deeper and the town provides a base for a string of high-powered businesses dedicated to the machinery of high finance.

Scattered along the Post Road and Riverside Avenue, and clustered at Greens Farms Road and Nyala Farms Road office complexes, financial firms are doing billions of dollars worth of business every day. And paying millions of dollars in real estate tax into the Town of Westport's coffers.

Close to a fifth of Westporters work in finance and insurance and not all of those professionals make the commute to Stamford or New York, it appears.

Here's a look at ten companies with serious financial clout in Westport.

1. Bridgewater Associates, LP: This colossus among hedge funds is headquartered at One Glendinning Place, off Weston Road. From its sylvan setting, the firm quietly manages $90 billion (yes, billion) in investments for its clients, which include foreign governments, pension funds and charities. The company has more than 1200 employees at its various offices in the town and is the ninth-biggest taxpayer. Boss Ray Dalio recently committed to set aside a large portion of his personal fortune to charity.

2. Phibro Trading LLC: Phibro, led by star trader Andrew Hall, was once a profit-making machine for Citigroup Inc. In late 2009, after Citigroup’s bailout, the commodities trading firm was sold to Occidental Petroleum Corporation for $250 million. Phibro, which trades everything from precious metals to sugar, has its HQ at the Nyala Farms Corporate Center and further offices in Europe and Singapore.

3. Oak Investment Partners: This venture capital firm, which also has operations in Palo Alto, Calif., and Minneapolis, has invested in more than 495 companies across a wide range of industries in its 33-year history. Oak’s investments in the retail sector include Whole Foods Market, Dick’s Sporting Goods and Office Depot, according to the company’s website. The firm is located at One Gorham Island, on the Saugatuck River.

4. MetLife, Inc: The giant insurance company has operated an office at Greens Farm Road since 1991 and currently 200 people work there in three divisions. MetLife’s Mature Market Institute, a research unit focused on aging, is also based at that location. In addition, the insurer is the parent company of New England Financial, which has a wealth advisory business on Post Road East.   

5. Compass Diversified Holdings: The NYSE-listed company (ticker symbol: CODI), which buys controlling stakes in other businesses, is located on Wilton Road. It currently has eight diverse subsidiaries including temporary staffing agency Staffmark which will soon have its initial public offering. Headed by I. Joseph Massoud, a frequent commentator on business television, Compass was listed on the stock market in 2006 and for 2010 it logged a net loss of $45 million.

6. Canaan Partners: A Silicon Valley venture capital heavyweight, Canaan has $3 billion under management. It has operations in California, India and Israel and recently opened a New York unit. Canaan’s Westport office is located on Riverside Avenue. Canaan has taken 52 companies to initial public offering, according to the firm’s website.

7. Allianz Group: The financial services behemoth is winding down its Westport-based Allianz of America, Inc unit. However the group will keep open the office at the Westport Corporate Office Park, on Greens Farms Road, for its real estate investment unit. Allianz owns the buildings at the office park, for which it has the seventh largest tax assessment in town.

8. Charter Oak Equity: This private equity firm located on Wright Street, invests in niche companies across a broad swathe of industries. According to the company’s website, Charter Oak Equity has seven companies currently in its portfolio and looks after three other investments from its predecessor funds. Charter Oak International Partners, which was formed in 2005, invests in smaller enterprises.

9. SL Financial Services Corp: Need to get funding for some big business purchases? Take a trip to the head offices of SL Financial, located on Riverside Avenue. The company, which focuses on equipment financing and leasing, has been operating for more than 10 years. It is part of LBBW, one of the largest banking groups in Germany.

10. First Equity Group, Inc.: This investor, also located on Riverside Avenue, has four diverse subsidiaries. It created First Aviation Services as a takeover vehicle in 1995, which, through acquisitions and expansion, has become one of the biggest aircraft parts suppliers worldwide, according to the company