Adding a bit more detail to the question: I'm keen to understand people's solutions for sending sensitive data (e.g. CSVs, PDF docs) to third party organisatio

Adding a bit more detail to the question: I'm keen to understand people's solutions for sending sensitive data (e.g. CSVs, PDF docs) to third party organisations that can only be assumed to have standard (MS Windows / MS Office) tools at their disposal for decryption. I'm keen for encryption to be of a modern, robust standard, and preferably available via mac / unix tools. Thanks HN!