ISO27001
The standard actually falls into two complimentary parts. ISO27001 and ISO27002. ISO27001 is designed to identify, manage and reduce the range of risks and threats faced by business. ISO27001 is a common sense, best practice, risk based approach to information security.
ISO27001 Standard
ISO27001 [ISO/IEC 27001:2005] sets out the requirements for an Information Security Management System (ISMS) and the Risk Management from which it is derived and on which the ISMS is based. An ISMS is a systematic approach to managing the security of sensitive information and covers not only IT but also policy, processes and people.
ISO27002
ISO27002 [ISO/IEC 27002:2005] (formerly ISO17799) provides a best practice, common and proven approach for developing high organisational security standards and effective security management practice. It provides for a series of best practice controls that organsations should deploy.