A System context element is a virtual container that includes the entire system and its actors.

You can convert any Block to System Context if you decide that the appropriate Block is decomposed. It may be called a system (i.e., Power Subsystem, Brake Subsystem, Lightening Subsystem).

System Context

Visibility representation

In SysML, properties and operations of the Block are public. Visibility representation literals, like +, #, ~, -, are not displayed in the Containment tree or in the element symbol on a diagram.

Converting a Block to System Context

To convert a Block to System Context


  1. Right-click a Block.
  2. Select Refactor > Convert To > More Specific > System Context.
    The Block is converted to System Context.