Patrick J. O'Brien has become a partner in the commercial development company of Callahan Pentz and a principal in the companion firm CPS, A Commercial Real Estate Company.

According to Joseph W. Callahan, Jr., co-founder of the firms, "Pat O'Brien has been a friend and financial advisor since I first became involved in real estate sales in 1973. He has been involved with CPS since its inception in 1976 as an independent accountant and financial and management consultant. We are delighted to have his financial expertise and management skills brought formally into the companies," Callahan said.

Pat O'Brien, 38, was born in Portland, Oregon, but lived most of his life in the San Jose area. He is a graduate of the University of Santa Clara, majoring in accounting and is a Certified Public Accountant.

He joined the accounting firm of Touche Ross in 1967, and has been in private practice since 1970. O'Brien was one of the founders of Pioneer Federal Savings and Loan Association in Campbell, CA, and served as chairman of the board for nine years. Pioneer recently merged into Home Savings of San Francisco, and O'Brien is a member of the advisory board.

O'Brien has also served on the Board of Directors for the Family Services Association of Santa Clara County and St. Joseph's School in San Jose.

Callahan Pentz specializes in the acquisition, development and management of office, industrial property. Callahan Pentz is the co-developer, along with The Prudential Insurance Company of America, of Hacienda Business Park and the developer of Valley Business Park in Pleasanton, and a number of other developments in the Bay Area. O'Brien has been an equity partner in the Valley Business Park development.

CPS, A Commercial Real Estate Company, is a real estate brokerage firm engaged in sales and leasing of commercial properties. The firms have offices in Pleasanton, Sunnyvale and San Francisco.

Pat O'Brien and his wife Jeanne live in Pleasanton. He has two children, Bridget, age 15, and Patrick K. O'Brien, age 13.

To see a reproduction of the original article and edition of Pleasanton Pathways, visit: January 31, 1984 Pathways.