First of all there is portfolio management where a product development strategy is defined based on information from the market and partner companies.
A good and relatively easy to use method for prioritizing software product requirements is the cost-value approach.
The assessment of values and costs for the requirements was performed using the Analytic Hierarchy Process (AHP).
In the approach of Karlsson and Ryan, five steps for reviewing candidate requirements and determining a priority among them are identified.
[3] Now, the cost-value approach and the prioritizing of requirements in general can be placed in its context of Software product management.