The book starts with a short account of Leibniz life, and then moves on to his philosophy of monads and the nature of mind and matter. Leibniz' idea that we live in the best of all. Jolley also explains Leibniz' views on human and divine freedom and the problem of evil. Leibniz' idea that we live in the best of all possible worlds was satirized by Voltaire, but Leibniz' worry seemed more about whether this allowed any freedom for the Creator. The final chapter looks at Leibniz' influence on later philosophy.
Jolley does a good job in bringing together work from many different places into a single book. In the end, however, the message I got was that Leibniz' philosophy is has little relevance to us today, or probably at any time. Hence it's hardly surprising that it hasn't had a lot of attention, and I'm not particularly motivated to find out any more about it. But if you do want to find out about Leibniz' philosophy then this book makes an excellent introduction.