Information is crucial for knowledge workers. You need information to perform tasks, take notes, prepare for meetings, and even to decide which tasks or projects to tackle first.

For many knowledge workers, finding this information is challenging. Notes are scattered across multiple notebooks, loose handouts from yesterday’s presentation that require further action, post-its with tasks on your tablet, a shared action and decision list from a project meeting recorded in minutes, various tasks listed in your task app, and your inbox filled with read, unread, flagged, and labeled emails spread across multiple folders.

Besides the information stored in various places, the non-recorded information might be an even greater source of stress. Information kept in your head that pops up at unexpected moments: promises made during phone calls, meetings still needing follow-up, casual commitments to colleagues to check documents, or brilliant ideas you had on the couch but haven’t written down yet. All stored somewhere in our powerful brains, which unfortunately aren't very effective at presenting this information at the right moment.

As a knowledge worker, you need information stored reliably outside your head to oversee your tasks, projects, materials, insights, and ideas. Without such an external system, you waste significant time and energy gaining an overview from numerous sources and your unpredictable brain.

Such a system helps you make better decisions and thus functions as a decision-support system. Deciding what and when to do becomes easier if you clearly see all available tasks. Locating project materials becomes effortless when your system is consistently structured.

Initially, a system like WorkFlowy, DEVONthink, or Evernote won't immediately feel familiar. At first, it may seem as if you're storing everything somewhere you might never revisit.

There are countless options to store relevant information: notebooks (Moleskine, Hobonichi, Leuchturm), cloud documents (Sharepoint, Google Drive, iCloud), note-taking applications (Evernote, OneNote, DEVONthink, Bear, WorkFlowy), mind maps (MindMeister, MindJet, MindNode), PKM Tools (Obsidian, Notion Logseq) or task managers (OmniFocus, Nozbe, Wunderlist, Todoist).

Your choice depends on personal preferences. Some passionately advocate for a specific type and format of Moleskine notebook, while others tirelessly praise task managers like OmniFocus. Decisions might also depend on your views on data storage locations. However, to become a truly reliable decision-support system, there are additional criteria to meet.

Below are seven requirements we believe a system must fulfill, collectively named "The Information Doctrine," developed over years of testing various methods, apps, sites, and tools.

Here are the seven requirements summarized, sometimes in words you might (yet) unsuccessfully search in a dictionary.

1 Information in a good system is storable
The logical first step is to capture information in your system. Conversations, reference emails, book notes, and chat messages with tasks or insights—all require external, reliable storage.

2 Information in a good system is searchable
Quickly finding a contact’s phone number or specific commitments made in conversations without flipping through notebooks or scrolling through numerous emails prevents distraction and wasted attention. Systems without effective search functionalities are inadequate.

3 Information in a good system is filterable
Sometimes you're searching not just for one piece of information but a selection relevant to your current context—such as reading materials or telephone tasks. Systems that allow quick filtering, like outliners or mail clients, show only contextually relevant information.

4 Information in a good system is organizable 
As the volume grows, information becomes overwhelming. Structuring information creates manageable chunks, categorizing notes by projects or clients. Many tools offer various structuring methods, from notebooks and tags to hierarchical outliners.

5 Information in a good system is reorganizable
Initial organization might not remain ideal for every purpose. Flexibility to reorganize information, easily moving tasks or notes for different contexts or presentations, is essential. Outliners and mind maps typically support easy reordering, unlike static documents or physical notebooks.

6 Information in a good system is metadata-capable
Beyond basic sorting and searching, adding metadata (tags or labels) allows multiple retrieval paths for the same information. Tags offer greater flexibility than folders by allowing multiple labels per item. However, consistent naming conventions and regular maintenance of tags are necessary.

7 Information in a good system is shareable
Collaboration is vital, requiring easy sharing of information with colleagues, clients, or project members. Good systems provide ways to grant access or export information to common formats.

8 Information is linkable
In the past few years, more and more information tools are providing the option to link information to another, like the links in Wikipedia or on the web. This is an important step up in the way to process information. This way information can be linked to another part of information just like our brain works. 

System speed is crucial. A perfect system you don't use due to slow loading or accessibility issues isn't useful. Quick retrieval or filtering actions are necessary to maintain workflow without friction. Cumbersome systems lead users to bypass official channels, resorting to personal spreadsheets or documents.

Ideas, insights, and questions appear at unexpected times, requiring a system accessible on mobile devices. Smartphones or tablets are ideal for quick look-ups or capturing brief notes on-the-go.

This is an English translation of a chapter of a book written by Arjan Broere, Mark Meinema, and Martijn Aslander.