Blockchain has been the subject of much hype, but does it really offer a potential solution to issues like disinformation and “disorders” of trust? This chapter examines the genesis and development of blockchain, addressing some of the common misperceptions and confusion about what blockchain is (and is not). Next, some of the touted properties of blockchain are considered – tamper-evidentiality, decentralization, transparency, and pseudonymity – with a focus on whether these produce the immutability needed to establish trust in the blockchain ledger. Given the conditionality of blockchain immutability, the chapter ultimately concludes it is inadvisable to view it in essentialist terms as a fixed and stable blockchain property. Rather, blockchain immutability is best viewed as a sustained commitment that a group of individuals holds onto because they believe that the attribute is desirable, even necessary.