This paper analyses money market developments since 2005, and examines factors that have affected money market functioning. We consider several metrics of activity in both secured and unsecured euro area money markets, and study interactions with new Basel III regulations and with central bank policies (liquidity provision, asset purchases and the Securities Lending Programme). Using aggregate data, we document that, prior to 2015, heightened financial market volatility coincided with worsening money market conditions, while higher central bank liquidity provision was associated with reduced money market stress