rked an important advance in musical set theory, the categorising of musical objects and their harmonic relationships. These have subsequently proved useful in audio system simulation and design and automated audio metadata tagging. Robert Moog was developing his Moog synthesiser at the same time. Lennart's genius is that he has done this work together with his work on dynamic systems, the branch of modern mathematics now dedicated to the modelling of large systems like financial markets and the weather - systems that change over time. Multimedia multiservice network provision including multimedia multiservice networks with integrated mobile metadata functionality increasingly exhibit large-system behaviour. This is not surprising given that they are large systems with multiple inputs, many of which are hard to predict. As with the weather, it sometimes seems hard to predict human behaviour, particularly long-term behaviour. This is, however, a scaling issue. We do not have enough visibility to the spatial, temporal and social data sets or the vector behaviour (direction and magnitude) of the data sets over a sufficiently wide range of time scales. The mechanics of mobile metadata potentially allow us to capture and manage this infor- mation and ultimately, provided user elective issues can be addressed, to realise value from the process. At this point, data on data (metadata) becomes more valuable than the data itself. Transaction-Centric Software 11.1 Financial Transactions Transactions are normally thought of as financial transactions. Many of them are, but a transaction can cover almost any exchange between two or more people or two or more devices and are normally enabled by some form of identification and trust-establishment protocol. However, let us start first with financial transactions and the role of mobile phones in the financial transaction process. Economic theory suggests that economic activity expands in line with population growth, particularly in developing countries. This may be true up to a po