 Hello, and welcome to this talk on efficient searchable encryption for joint queries. This is joint work with Charanget. The advent of Cloud computing allows outsourcing the storage and processing of extremely large databases to third-party Cloud Service providers while retaining the ability to process queries over them. This is simple and efficient if the Cloud Service provider is trusted, but this is not always the case. In order to ensure data privacy, a client might want to encrypt the data before outsourcing it to the Cloud. This poses a challenge. How do we query the encrypted database directly without decrypting it first? Searchable Symmetric Encryption or SSE in short, is a special class of encryption schemes that allow querying and updating symmetrically encrypted databases in an efficient manner while revealing very little information to an honest but curious server. In this paper, we propose joint cross tags or JXT in short, a new practical efficient SSE scheme that supports equi-join queries over pairs of encrypted tables in an encrypted relational database. Here is a one-slide example of an equi-join query. We have two tables, one for transactions and one for merchants, with transaction ID serving as the joint attribute, and we wish to find all records in the join of these two tables with date being January 2022 and merchant name being Apple. JXT supports such queries without any pre-processing of joins, and with some additional storage overheads, which are proportional to the number of join attributes. This is typically small in practice. JXT is a purely symmetric key primitive, which makes it practically efficient and highly scalable to extremely large encrypted databases. JXT is in fact the only SSE scheme till date to support join queries with no pre-processing of joins, and while allowing flexible table updates. In particular, JXT avoids storage blow-ups due to explicit join computations while allowing tables to be set up and updated independently without any re-computation of joins. JXT incurs a default storage overhead, where T is the number of designated join attributes. T is typically small in practice as the join attribute would be the primary or secondary key of a table. In terms of such overheads, JXT incurs a linear communication overhead and linear computation overheads at the client, while outsourcing the heavy quadratic computational overheads to the server. Finally, JXT is fully compatible with state-of-the-art SSE schemes for Boolean queries, such as Oblivious Cross Tags, and can be used in conjunction with such schemes to support rich Boolean queries over joins of encrypted tables in encrypted relational databases. For more details on the construction and leakage of JXT, do tune into our talk at Asia Crypt on Wednesday. Thank you and see you at Asia Crypt 2022.