“Linking by inking” is a new interface for reader-directed link construction that bridges reading and browsing activities. We are developing linking by inking in XLibris,™ a hypertext system based on the paper document metaphor. Readers use a pen computer to annotate page images with free-form ink, much as they would on paper, and the computer constructs hypertext links based on the ink marks. This paper proposes two kinds of reader-directed links: automatic and manual. Automatic links are created in response to readers’ annotations. The system extracts the text near free-form ink marks, uses these terms to construct queries, executes queries against a collection of documents, and unobtrusively displays links to related documents in the margin or as “further reading lists.” We also present a design for manual (ad hoc) linking: circling an ink symbol generates a multi-way link to other instances of the same symbol.