Understanding the source of funds being used in a transaction is a key protection for your firm. Legal Sector Affinity Group (LSAG) guidance encourages you to approach it as an opportunity to protect your firm from being used for money laundering. Money Laundering, Terrorist Financing and Transfer of Funds (Information on the Payer) Regulations 2017, SI 2017/692 Requirements in relation to establishing the source of funds/wealth are contained in the Money Laundering, Terrorist Financing and Transfer of Funds (Information on the Payer) Regulations 2017 (MLR 2017), SI 2017/692. MLR 2017, SI 2017/692, require you to establish the source of funds involved in a transaction: • in relation to ongoing monitoring (where necessary) (MLR 2017, SI 2017/692,