Two homelessness charities want to build specialist houses to get people off the streets permanently.
Business leaders and philanthropists gathered at Notts County's football ground to be told how their money could help.
The plans are supported by Nottinghamshire Community Foundation - a charity set up to encourage philanthropy for the benefit of the county.
Emmanuel House and The Friary explained their plans to build two "specialist units".
Each unit, one for men and one for women, would house four to six people.
Denis Tully, chief executive of Emmanuel House, said: "We have a crisis. If you present yourself as homeless, you have to meet a threshold before being offered support.
"We give shelter regardless of circumstances and we want to provide quality accomodation.
"We want to build these units to give accommodation, support, choice, control and skills to [people] be able to move on and gain back their independence."
The houses, which would cost around £120,000 each to build, would take people off the streets as soon as they had been identified and allow them to be supported while living in their own homes.
A 48-year-old man who has spent periods of his life living rough on the streets of Nottingham addressed the gathering.
He said: "These plans are so important. I was living rough as a teenager and 'scary' isn't the word; you literally feel like the lowest of the low and that's how people also treat you.
"Taking people off the streets and putting them into private housing is all well and good but if they don't have support and help after that, it is worth nothing.
"My friend was put in a house and he killed himself. We need to build these houses and have support in place for people so that they know they are not alone afterwards."
The event was aimed at 100 of Nottingham’s most successful entrepreneurs to warn them about the plight of vulnerable people and how they could help.
Sam Crawford , chief executive of The Friary, said: "This is a local and national crisis. It isn't just about the statistics; each statistic is a person's life."
Nina Dauban, chief executive of Nottinghamshire Community Foundation and host of the event, said: “We recognise that many people want to make a difference and give generously to charity.
"We also know that giving to local charities offers greater benefit to our communities. Here today we are giving them opportunities to give locally and help us build social housing for people who have no home.
"One hundred years ago, dozens of almshouses were built in Nottingham by local families for those in need then, namely the elderly.
"Today, the need is to do this again but this time for people under 55 and we are launching an exciting campaign today to do exactly that.
"We already have several donors interested in helping and are sharing information today to inspire others”.
Nick Ebbs, the county's High Sheriff, added: “Having a roof over your head and a secure place to call home is vitally important to all of us. It is not possible to flourish without. I am an enthusiastic supporter of this very important campaign.
"Homelessness is nasty. If you get there, you have hit rock bottom."
