This paper describes work-in-progress on an Interactive Sonification Toolkit which has been developed in order to aid the analysis of general data sets. The toolkit allows the designer to process and scale data sets, then rapidly change the sonification method. The human user can then interact with the data in a fluid manner, continually controlling the position within the set. The interface used by default is the computer mouse, but we also describe plans for multiparametric interfaces which will allow real-time control of many aspects of the data. Early results of interactive sonic analysis of two example domains are described, but extensive user tests are being planned.