Thomas Warren Sears was born in 1880 in Brookline, Massachusetts. He received a Bachelor of Arts degree from Harvard University in 1903 and Bachelor of Science degree in landscape architecture from the Lawrence Scientific School of Harvard in 1906. Sears was an amateur photographer who won awards for his photography while at Harvard. In 1915 his images were published in the monograph, Parish Churches of England. After graduation he worked for the firm of Olmsted Brothers Landscape Architects for two years and then briefly practiced in Providence, Rhode Island. In 1913, Sears established a landscape design office in Philadelphia, Pennsylvania where he spent the remainder of his professional career. Sears at one point was in a professional partnership; some of his design plans list the firm name of Sears and Wendell. He was made a Fellow of the American Society of Landscape Architects in 1921.
Sears designed many different types of landscapes ranging from private residences, schools, and playgrounds to parks, cemeteries, and urban housing developments. His designs were primarily located in Pennsylvania, Maryland, and New York. Just a few of his private landscapes include Marengo in Easton, Maryland; Sunnybrook, the Isaac H. Clothier, Jr. estate in Radnor, Pennsylvania; and Balmuckety in Pikesville, Maryland. In 1915, Sears started work on Reynolda, a country estate in Winston-Salem, North Carolina. He generated design plans for the property intermittently over the next two decades. Reynolda's formal gardens, greenhouses, and acres of fields and woodlands subsequently became part of Wake Forest University.
During World War I, Sears designed Army camps in Battle Creek, Michigan and Spartanburg, South Carolina. He also helped lay out Langley Field, at that time an experimental aviation field in Hampton Roads, Virginia. In the 1940s, Sears designed the amphitheater at Swarthmore College in Swarthmore, Pennsylvania for concerts, outdoor performances, and other special events. During that decade he also worked on Colonial Revival gardens at Pennsbury, William Penn's country estate in Bucks County, Pennsylvania located by the Delaware River. Sears retired in 1964 and died in 1966.