There are many definitions of Knowledge Management, but the one we prefer is the simplest - "Knowledge Management is the way you manage your organisation, when you understand the value of your knowledge". In other words, it is the management framework (of Roles and Accountabilities, Processes, Technologies and Governance) that you put in place to maximise the value and application of your knowledge, and which provide a managed approach to building, developing and retaining know-how, in service of business goals.
Knowledge Management is about systematically making use of the knowledge in the organization, and applying it to YOUR business problem; tapping into 'What your company knows' to help you deliver your business results. It consists of never making the same mistake once (let along twice), and making every decision in the light of the full knowledge base of the company. The management of knowledge needs to be part of your business practices, just like the management of finance and the management of safety.