The Rules contained in this Module are aimed at ensuring proper protection of client assets to minimise the risk of client assets being used by investment firm licensees without the client's written consent (except to the extent permitted by the Rules) and to restrict the commingling of client assets with investment firm licensee assets. This Module builds upon Principle 6 — Customer Assets (see Module PB (Principles of Business)). Principle 6 requires investment firm licensees to take reasonable care to safeguard the assets of customers for which they are responsible.