1. We think it's important that users be able to put a single item into multiple collections
2. We think it's important that users be able to see all the collections an item belongs to from the item (aka bi-directional references)
3. We want Chandler to look and feel like a standard PIM
4. We believe that users think in terms of projects, not applications or data types
5. Users should make decisions when they're ready to

What is the fallout of these assumptions?

• Assumption 1
• We think it's equally important that users be able to put a single collection into multiple collections
• As a result, there's no such thing as a fixed hierarchy of collections
• Instead, Chandler is a faceted classification system
  • Columns in your table view is a faceted system
  • iPod is a faceted system

• Assumption 2
• Chandler collections are attribute-centric
• Attribute-centric collections need to have clear semantics
  • What kind of a grouping is this? Kind-based? Project-based? Status-based?
  • If it's Project-based, what defines the project? A person? A product area? An aspect of your organization? A project phase?
• Otherwise, you end up with a sea of tags (ie. flickr or delicious)

• Assumption 3
• We need to have kind-based application areas: Mail client, Task manager, Calendar
• We need to have a sidebar where users can organize items into user-defined groupings

• Assumption 4
• Users need to be able to create groupings of items irrespective of Kind.
• As a result, groupings are orthogonal to Kind. What grouping an item and what kind an item is are simply 2 independent facet of that item.
• In other words, groupings are not children of Kind. There is no static hierarchy.

• Assumption 5
• Users shouldn't have make a priori decisions about what Kind of grouping they should make (ie. Calendar, Tasklist, Mailbox etc)
• All groupings are potentially cross-Kind from the get-go
• Groupings become relevant to Kind areas as users add items of those Kinds (ie. Home becomes a Mailbox as soon as the user adds mail items to Home)
• Something we don't want to emulate from traditional PIMS is their penchant for long list of grouping types: Local folders, IMAP folders, Public folders, Saved searches, Mail filters, Kind-based views, Projects, etc