title: Is programming a master password a good idea for a PHP based login system?
body: <p>I have an area of my system where clients can login to view information about their account. The login system is secure (I hope) and uses the latest PHP standards (e.g. <code>password_hash</code>, <code>password_verify</code>, etc).</p>
  
  <p>There's often the need for me to login to a client's account for a variety of reasons but obviously I don't know their password (and I don't want to know it either). Would it be safe for me to program a master password that allows me to login to any account using the same password?</p>
  
  <p>I would like opinions on ethics, affect on security, etc.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>Both the clients access and my access is read only.</p>