Above: The Documentcloud application helps digest records for journalists. Mark Horvit is executive director of Investigative Reporters and Editors, which hosts DocumentCloud, and Ted Han is lead developer of DocumentCloud, a 2009 and 2011 Knight News Challenge winner.

Working on DocumentCloud has been thrilling and humbling.

Hundreds of news organizations on every continent except Antarctica have used the platform to upload just shy of 15 million pages; that’s 1.1 million documents. They are using DocumentCloud to analyze those documents, add comments to provide deeper meaning, and put the material in the hands of the public.

And the public is paying attention: Readers have viewed those documents more than 200 million times.

What have they been reading? Everything from Sarah Palin’s emails to copies of the U.S. Supreme Court’s Obamacare ruling annotated by legal experts. From Wikileaks memos to audits of the local sheriff’s department. From Edward Snowden’s leaked documents to municipal budgets.

Quantity isn’t always quality; we’re fortunate to have both.

Hundreds of news organizations have been using DocumentCloud for award-winning, difference-making reporting since 2009, when it received an initial Knight News Challenge grant. The Guardian used DocumentCloud as a key element of its interactive coverage of the National Security Agency. The Lens, an online investigative organization in New Orleans, just launched The Vault, which allows citizens to examine city contracts.

The service has grown quickly, adding users throughout the world. We launched a Spanish-language version last fall and can handle documents in an increasing number of languages.

The focus has always been on transparency, not only by shining a light on documents often shrouded in government secrecy, but in allowing the audience to evaluate journalists’ work by reading the source material for themselves.

A key focus for us now is sustainability. DocumentCloud has been a free service since its inception, available to all news organizations, regardless of the size of their operating budgets. But limited resources have meant that we haven’t been staffed at a level that allows us to make needed upgrades and additions. It also means we’ve relied entirely on grant funding, which isn’t a model for long-term survival.

The trick now is to uphold that tradition while finding ways to generate the income necessary to thrive. And thanks to a new $1.4 million grant from Knight Foundation, we have the resources to tackle that challenge.

Our goal is to keep the core service free. The idea is to build additions and enhancements that we can charge for, while allowing journalists to continue to upload, analyze, annotate and publish documents at no cost.

As part of the process we’ll make improvements to the core service and add features, many of which have been requested or inspired by our users.  Among the features we’ll be working on are a mobile-friendly document viewer and additional automated analysis tools. We develop our tools and platform in the open and are excited to work with users as we move forward on making sure DocumentCloud remains a tool for transparency as long as there are documents to be freed.