The success of the decentralised internet depends on robust building blocksfor decentralised identity, reputation and communication in general. We'lllook at how Matrix.org (an open standard for decentralised communication) isattacking these problems - both now and in the future. Matrix is an open source project that publishes a standard and reference FOSSimplementations for decentralised communication, primarily focusing ondefragmenting all the various communication silos (messaging, VoIP, IoT etc)that users are trapped in today. We believe that no single company or entityshould ever have ownership or control a user's conversations - only the userthemselves should have control. In Matrix today rooms are replicated over all the servers which participate ina given conversation, decentralising by default similarly to Git orblockchain. Unlike other protocols, rooms have no single point of control on agiven domain or entity and conversation history is shared equally over allparticipants. However, user accounts themselves are currently bound to asingle 'home server', meaning that users are currently tied to a singleservice provider, similarly to email or XMPP. In this talk, we'll discuss Matrix's plans to decentralise accounts too -letting users share their account data across whatever sets of servers theytrust; providing account portability as a matter of course. We'll also discussthe related topic of decentralised identity - how to track how emailaddresses, phone numbers and other identifiers map to a given matrix user...without maintaining a centralised ID mapping database. Finally, we'll explore the critical topic of decentralised reputation. Anydecentralised system, whether it's Matrix, Email, XMPP, blockchain etc needs away of tracking the relative reputation of the participants in the system inorder to let users filter undesirable content. We see this as the singlebiggest challenge remaining for Matrix, and one that is vital to the internetat large - helping users self-curate the content they consume and breakingfree of the echo-chamber effect of centralised services. We'll talk about theoptions we've been looking at with Matrix, and issue a call to arms for thewhole community to work on solving this problem.