A method for controlling a computer having a processor, a memory, a display and a user input device to respond to a request for a content use right, the method comprising: (a) storing in the memory a plurality of right records, each right record representing a right for a predetermined type of content use; (b) storing in the memory a plurality of display rule records, each display rule record being linked to a type of content use and having program code for controlling the display to prompt for at least one predetermined parameter and for receiving input from the input device representing a value for the parameter; (c) storing in the memory a plurality of right rule records, each right rule record being linked to a right record and performing one of determining whether the linked right is granted, determining a price for the right and determining a royalty for the right; and (d) controlling the processor with a rules engine program to select a display rule record for a requested content use and to run program code therein to obtain parameter values and execute program code in right rule records linked to the selected right to determine, based on the obtained parameter values, whether the right should be granted, the price for the right and the royalty for the right and subsequently, if applicable, selecting a single right from a plurality of valid rights (e) comprising storing in the memory a plurality of parameter records, each parameter record defining a predetermined parameter value, and linking parameter records to right rule records so that when program code in a right rule record is executed, parameter values required by the executing program code are predefined by the linked parameter records. (a) storing in the memory a plurality of right records, each right record representing a right for a predetermined type of content use; (b) storing in the memory a plurality of display rule records, each display rule record being linked to a type of content use and having program code for controlling the display to prompt for at least one predetermined parameter and for receiving input from the input device representing a value for the parameter; (c) storing in the memory a plurality of right rule records, each right rule record being linked to a right record and performing one of determining whether the linked right is granted, determining a price for the right and determining a royalty for the right; and (d) controlling the processor with a rules engine program to select a display rule record for a requested content use and to run program code therein to obtain parameter values and execute program code in right rule records linked to the selected right to determine, based on the obtained parameter values, whether the right should be granted, the price for the right and the royalty for the right and subsequently, if applicable, selecting a single right from a plurality of valid rights (e) comprising storing in the memory a plurality of parameter records, each parameter record defining a predetermined parameter value, and linking parameter records to right rule records so that when program code in a right rule record is executed, parameter values required by the executing program code are predefined by the linked parameter records.