contract in order for the
transaction to be considered valid. Hence, the endorsement policies define the
organizations (through their peers) who must “endorse” (i.e., approve of) the
execution of a proposal.</p>
<p>### Modification policies</p>
<p>There is one last type of policy that is crucial to how policies work in Fabric,
the <cite>Modification policy</cite>. Modification policies specify the group of identities
required to sign (approve) any configuration _update_. It is the policy that
defines ho