Sam Jones, president of Wairarapa Parents Centre, said the event is about promoting breastfeeding as the best option for babies.
"It's good bonding between mum and baby, antibodies are passed through from mum to baby through milk, it's a live substance and each mother's breast milk is unique for each baby," Ms Jones said.
The event also brings the community together, as new mothers go from working full-time to being at home alone, which can be isolating.
"We're wanting to help mums to support each other with breastfeeding," Ms Jones said.
Mum Haylee Olds said she is heading along to The Big Latch On for just that reason: "I think it's the best start for baby, I really enjoy it, so I'll go along to support everyone else."
The event is open to breastfeeding mums, with toys for pre-schoolers and food and drink.
The Big Latch On, August 3, 9.30am to 11am, Senior Citizens' Hall, corner of Cole and Perry St, Masterton.