Non-inviteA project or initiative that kicks off without inviting an individual who may have a right to be recognized as a stakeholder. This risks having the project derailed because stakeholders weren't properly consulted.
DetachmentInviting an individual to participate but failing to register or discuss their issues and assigning them only non-critical tasks. For example, saying "yeah, that's true" when an individual complains of a problem but not following up or logging the issue.
DistractionAllowing or encouraging an individual to work on non-critical work items in order to distract them from more important work. For example, a software architect who is viewed as difficult to work with such that they often slow projects down may be encouraged to work on an architectural roadmap as opposed to critical business projects.
Formal SideliningUsing your authority to remove an individual from a project. Often done to reduce resistance to change and empower agents of change. For example, if a project team has 5 developers and one developer has taken on a defeatist attitude by regularly suggesting that the project is hopeless and worthless, that developer may be removed by management to work on a less critical project.
Counter-tacticThe primary counter-tactic for sidelining is to push your way in to the center of the action to become an agent of change. Taking on difficult work assignments and being generally useful typically prevents you from being sidelined. It is rare for those who produce significant value to be sidelined as this is hard to defend.
A political tactic that involves ignoring, distracting or removing the opposition so that they no longer play an active role in a program, project, initiative, team or function.
An analogy to the sidelines of a sports field where players who are not in the game sit or stand.