Distributed storage systems have now become mainstream, partly due to exponential growth in data volumes. It is common for applications nowadays to access data that is partitioned or sharded across many nodes, and in addition, partially replicated. Large Internet companies further deploy applications that span multiple data centers.For a few years, it was common to settle for weak consistency in such settings, adhering to the so-called "NoSQL" approach. Indeed, an article that appeared in this column four years ago 1 reported a "fear of synchronization" among chief architects who had built large-scale distributed systems in industry. But in the past couple of years, we see this trend reversing. Both academic and industrial projects have recognized the need for strong consistency and so-called ACID transactions in large distributed storage systems. Such strong consistency is the topic of the current column.Our first contribution, by Dahlia Malkhi and Jean-Philippe Martin explains the concurrency control mechanism of Google's Spanner system. Our second contribution, by Ittay Eyal, discusses more generally fault-tolerant architectures for distributed ACID transactions. Many thanks to Dahlia, Jean-Philippe, and Ittay for their contributions! Farewell. On a personal note, this is my last issue as editor of the distributed computing column.