A review into Labour's historic links with trade unions has recommended more transparency while retaining the party's federal structure.
A document drawn up by former Labour and union official Lord Collins will be debated by the party's national executive next Tuesday ahead of a special conference on March 1.
A series of recommendations are included in the report, including changes to the voting strengths of unions, MPs and constituencies in the election of Labour's leader.
Ed Miliband won the last leadership election largely thanks to support from unions, but he announced changes to the links following controversy over union involvement in the selection of a Labour candidate in Falkirk last year.
Mr Miliband said he wanted union members to opt in to join Labour rather than be automatically affiliated.
The Collins report, seen by the Press Association, reads: "Trade unions and other affiliates should continue to have a collective constitutional role inside party structures, but on a more transparent basis.
"After a transitional period of five years, affiliation fees shall only be accepted on behalf of levy payers who have consented to the payment of such fees.
"At that point, the scale of a trade union's collective affiliation shall be governed by the number of levy payers who have consented to the payment of affiliation fees."
A section headed "closer relationship with trade unionists" says: "Levy paying trade unionists should have the ability to become affiliated supporters and to receive certain individual rights, by signing up to Labour values and providing the party with verifiable personal details.
"These individual rights should include the right to be attached to a CLP (constituency party) and to vote in leadership elections. They will not be able to represent the Labour party or to participate in the election of party representatives - with the exception of primaries and leadership ballots - unless they join as full members.
"Party systems should be in place to enable a new category of affiliated supporters to be established before the end of 2014."
Lord Collins said in his report that the current Electoral College for leadership elections should be abolished and replaced in party rules by a new system based on the principle of one member one vote (Omov).
"Multiple voting in leadership elections should be ended. The eligible electorate should be composed of members, affiliated supporters and registered supporters.
"Members of affiliated organisations who are not already party members may take part in the ballot if they register with the party as affiliated supporters.
"This will require them to declare their support for Labour values, provide the party with personal contact details and be on the electoral roll.
"Individuals who are not already party members or members of an affiliated organisation may take part in leadership elections by registering with the party as a supporter. This will require them to declare their support for Labour values, provide the party with personal contact details, be on the electoral roll and pay the party a fee."
Responsibility for nominating and shortlisting leadership candidates shall remain with MPs.
Individual trade unionists will no longer be automatically affiliated through the payment of the political levy, but they will be able to take part in elections if they choose to join a new category of affiliated members for a fee of £3.
Mr Miliband said these were the biggest changes to who could become involved in the party since its formation.
Many union officials and Labour MPs have been unhappy that so much time and energy has been spent over the past few months on discussing the link between the two wings of the movement, which some believe was unnecessary.