* As a direction: Southeast is not capitalized when used as a direction.
* Example: "The wind was blowing from the southeast."
* As a region: Southeast is capitalized when referring to a specific geographical region.
* Example: "The Southeast is known for its warm climate."
* As part of a proper noun: Southeast is capitalized if it's part of a proper noun, like the name of a company, organization, or place.
* Example: "The Southeast Asian Games are held every two years."
In short, think of it this way: If you're referring to a direction, don't capitalize it. If you're talking about a specific region or part of a proper noun, capitalize it.