One in three customers would be more likely to buy spirits and mixers if pubs were better at serving them, a survey suggests.
And three quarters said the quality of spirit and mixer drinks they are served in pubs is no better than what they could create at home.
The survey, commissioned by Diageo and based on 1,010 interviews, influenced the firm's summer marketing activity around core brands including Smirnoff, Gordon's and Pimm's.
Russell Jones, director of category marketing for Diageo GB, said the results were a concern for licensees hoping to sell more in the summer months.
"It's a real worry when you are asking people to pay £3 for a mixed drink," he said.
Diageo's new campaign to celebrate the 'spirit of summer' will include simple five-step diagrams to help pub staff to create perfect serves as well as posters displaying the price of drinks.
"There's a perception that spirits are more expensive than they really are," said Jones.
"Clearly displaying the finished drink price will help. Licensees also said displaying pictures of finished drinks more than doubles the likelihood of seeing increased sales."
One thousand point-of-sale kits will be distributed to pubs and bars and Diageo staff will work with licensees to maximise spirit-and-mixer sales between May and July, with a focus on sales during Bank Holidays.
This will include developing a range of long, mixed drinks suitable for specific venues, and promoting 'hero' drinks - such as Smirnoff mules (Smirnoff and ginger ale), Gordon's and tonic and Pimm's - on a weekly or monthly basis.