It can sometimes seem a mystery why some couples stay together and thrive - while many more split up or drag on scratchily.

Fortunately, though we might ascribe happy love to chance, there are a range of identifiable secrets that underpin all good relationships and that we can learn and put into practice.

This book teaches us the key ingredients of contented love in a tone that's warm, encouraging and often funny: how to communicate effectively, how to manage differences, what to do when sexual problems arise, how to air grievances, the best way to share a home and - when things grow truly problematic - how to judge whether or not we should stay or leave.

This book shows us how to take the necessary, careful, intelligent steps towards the contented love we deserve.