Question: Is there an XML editor that can help me with single-source publishing and supports multiple frameworks like DocBook and DITA?

If you're in the market for an XML editor that supports single-source publishing and multiple frameworks like DocBook and DITA, Oxygen XML Editor is a top pick. It's got a broad range of XML authoring and development tools, including XML schema modeling, smart XML editing and XSL/XSLT support. On top of that, it's got single-source XML publishing with visual WYSIWYG editing, so it's good for managing content that spans multiple formats and frameworks. You can find a version to suit your needs, from a lightweight standalone app to a full-featured plugin for Eclipse.

Another top contender is Altova, which includes XMLSpy, a professional XML and JSON editor with a lot of tools for modeling, editing, transforming and debugging. Its suite also includes StyleVision, a report builder and XSLT stylesheet design tool for generating reports and forms from XML data. Altova offers a free, fully-functional 30-day trial, so you can try it out before you buy. That's great for figuring out if their tools are what you need for XML and JSON editing.

If you need to manage more than just a few types of content, Quark has a suite of tools for creating, managing and delivering content across multiple stages and formats. Its Content Automation and Content Intelligence components offer AI-powered insights and analytics to help with targeting and personalization. Quark's tools are geared for a variety of industries and use cases, including structured authoring techniques, so it's a good choice if you have different content management needs.