Parliament decided that all files would be released after a debate in the House of Commons on Monday.
"It's a fantastic success for the families," said Dalglish. "It's a huge step forward for them. They are getting access to what other people have seen, the papers that are there.
"There has been some fantastic work done by Andy Burnham and Steve Rotheram. Andy came up two years ago and said he'd try and push this forward and he's kept his word. Steve Rotheram is a local MP who's pushed it forward, so there are lots of people who've done brilliantly for the families."
The debate came about after 140,000 people signed a government e-petition to have the documents disclosed to the public.
"The petition tells you this isn't just about Liverpool Football Club and the fans who support Liverpool, it's about football," Dalglish added. "It could have been anybody there. Everyone who supports a football club realises."
The date that the files will be handed over to the families of the 96 Liverpool fans that died in 1989 has not been set.