As part of a ramp-up in its structure, following the recruitment of Pat Symonds last year as its new chief technical officer, the Grove-based outfit has signed a number of leading engineers.
Jakob Andreasen joins from Force India as head of engineering operations, while Craig Wilson returns to the team from Mercedes as head of vehicle dynamics.
Rod Nelson, who was previously at Lotus, will head up Williams' testing operation.
Symonds said: "Williams is determined to make strong improvements in our competitiveness over the coming seasons and these new appointments continue our aggressive approach in recruiting some of the sport's best talent."
Williams is also expected to announce soon that Ferrari's Rob Smedley is to join it in a senior engineering role, but this has not yet been confirmed.