Advertising agency Allen & Gerritsen has moved from Watertown to Boston’s waterfront Innovation District. The 130-employees firm, which said it plans to add as many as 50 new employees over the next several years, made the move “to expediate the company’s strategic growth plan.”

The move is another indicator of the growing status of the South Boston waterfront as a business location.

“Allen & Gerritsen is another hugely creative company moving to Boston’s waterfront,” said Boston Mayor Thomas M. Menino, said in a statement. “But they are more than that: a&g is a great champion for the Innovation District, for Boston’s energetic workforce, and for their dynamic clients.”

The move is “the culmination of years of planning, preparation, and hard work,” said Allen & Gerritsen chief executive Andrew Graff. “We are beginning the next chapter in our history by moving into a vibrant environment where we can fearlessly innovate, create, explore and grow.”

In making the move, a&g joins Boston ad agency PARTNERS+simons, which trailblazed a path to the waterfront Marine Industrial Park 18 years ago.

“We moved because the rent was low and because the environment would be stimulating -- free of the distraction of trendy bistros and boutiques,” said PARTNERS+simons chief executive Tom Simons. “The changes in the past 10 years have been remarkable. It’s definitely the new Boston. The rent’s not as low anymore, but it’s still a great place to grow an agency. We welcome Allen & Gerritsen to the neighborhood.”