Undercooked chicken. Poor customer service. A bug in the guacamole.

For years, users on the popular review Web site Yelp have had the final — and only — word when reviewing their most-loved or most-hated local restaurants, clothing shops and beauty salons.

Now business owners are getting their chance. And talking back is sweet.

This month, Yelp will open up its site to public responses from businesses, a first for the 5-year-old San Francisco company. It’s a significant victory for business owners, who have long griped that they were being shut out of the Yelp community — which boasts more than 5 million reviews to date — and were unable to address what they perceived as unfair and unchecked posts.

For small businesses, which rely on good word of mouth, a negative review could be especially damaging.

“A lot of times you read the reviews and you read something bad and it’s out of your control,” said Pablo Brea, general manager at Lala’s Argentine Grill in Hollywood. “If someone comes in and says, ‘I don’t like the food,’ there’s nothing I can do about it.”

“It gives you a second chance,” he said.