A one-off chat forgets everything the moment you close it. That is fine for a quick question. It is a pain for work you come back to: the same client, the same report, the same pitch, week after week. You end up re-pasting the same background every single time.
A Project ends that. Think of it as a home for one piece of work, where the context is always already in the room. Open a new chat inside it and Claude starts out knowing the brief, the files, and the history, before you type a word.
A quick heads-up on the word "project." This lesson is about Projects in Claude's Chat. Claude also has Cowork, now built right into the same Claude app: you pick Chat or Cowork from the same message box. Cowork has its own Projects, which live on your computer and organise the work Claude does on your files. Those are the next lesson (4.4). Same word, two homes, so it pays to know which one you are in.
What a Project holds
A Project keeps three things together:
- Knowledge. Files you upload once: the brief, the brand guide, past examples, the data. Claude reads from these in every chat in the project.
- Instructions. A standing brief for this work: who it's for, the goal, the tone, what to avoid. Set once, applied to every chat inside.
- Chats. Its own history. All the conversations about this work live here, not scattered across your sidebar.
Why it beats a one-off chat
Back in lesson 2.5 you met three places to put context: this message, this project, everything (your profile). The Project is the middle scope, and it is the one people underuse. Broader than a single chat, so you do not repeat yourself. Narrower than your profile, so this work's context does not bleed into every unrelated chat you have. When a body of work has its own world, the Project is where that world lives.
Good news on access: Projects are free for everyone. Free accounts can keep up to five; paid plans lift that and add the scaling trick below.
Setting one up
It takes a couple of minutes:
- Make a project and give it a clear name ("Acme account", "Q3 board report").
- Add the knowledge. Drop in the documents this work leans on. Same uploads as any chat, up to 30 MB a file, and the lean-format tip from 2.5 still pays: prefer
.mdor.txtfor big reference material. - Write the instructions. The same five-line brief from 2.5 (who, goal, audience, style, watch-outs), scoped to this work.
- Start chatting. That's it. Every chat now begins with the full picture.
It scales past a single window
Here is where a Project quietly outgrows a normal chat, and it connects straight to lesson 4.1. In an ordinary chat, everything you add competes for the same desk space. Pile on enough files and the window fills.
On a paid plan, a Project handles this for you. When the knowledge base gets large, Claude switches to retrieval (the technique is called RAG): instead of loading every file onto the desk at once, it searches your knowledge and pulls in only the parts that matter for the question in front of it. That lets a project hold far more reference material, up to roughly ten times more, without the window ever clogging.
On a free plan there is no retrieval, so keep a project's knowledge modest and it works fine. Either way, the habit is the same: give the project what the work needs, and keep it current.
Keep it tidy
A project's knowledge is a fridge, not an attic. Things go off. Remove files that are out of date, or Claude will happily quote last quarter's numbers. Keep the instructions short and current, a bloated brief works worse than a tight one. And give each real piece of work its own project rather than dumping everything into one; a project about "everything" is a project about nothing.
Sharing with a team
On Team and Enterprise plans, a project can be shared with colleagues, as view-only or full edit. Now the whole team works from the same knowledge and the same brief, which is the closest thing to a shared playbook Claude offers. On Free, Pro, and Max, a project stays yours alone.
Where this goes next
Put lessons 4.2 and 4.3 together and you have the power-user setup: Skills are how a job gets done your way; Projects are where a body of work lives, with its context on tap. Next, in lesson 4.4, we leave the chat window entirely: Cowork lets Claude work directly on the files sitting on your own computer.
Try it
Pick something you come back to often: a client, a recurring report, an ongoing pitch. Make a Project for it. Add two or three files it always needs, and write a five-line instructions brief.
Now open a fresh chat inside the project and ask for something real, without pasting any background. Watch it answer as if it already knew the whole story. It does, because you told it once instead of every time. That is the whole point of a Project.
(General exercise. Role and industry versions come once accounts are in.)