This week, President Obama made several recess appointments to the National Labor Relations Board and the Consumer Financial Protection Bureau. But here’s the catch: The Senate was in session, not in recess. As Heritage’s Todd Gaziano and Edwin Meese argue, President Obama’s unilateral determination that the Senate’s pro forma sessions were not real undermines the separation of powers.
This is the opportunity to remember what the separation of powers is and why it matters.
The principle of separation of powers states that the executive, legislative, and judiciary powers of government should be divided into different branches and not concentrated in one. These departments should be separate and distinct because of the corrupting nature of power. If the body that made the laws could also enforce them and adjudicate disputes, it would likely do so in a preferential manner, undermining the rule of law and basic fairness. Power, in other words, must be checked, or it will be abused. In the Federalist Papers, James Madison calls the combination of legislative, executive, and judicial powers “the very definition of tyranny.”
The Framers did not think that merely separating powers on paper would do the trick. The Constitution gives each branch of government some powers over the others to permit it to resist encroachments. For instance, the veto power gives the President a check on Congress. The Constitution therefore not only divides power but also sets it against itself, thereby creating a dynamism within the workings of government that uses the interests and incentives of those in government to enforce constitutional limits.
The separation of powers doctrine also intends to improve the energy and efficiency of government by allowing each branch to specialize, in effect, in order to fulfill its unique function.
This question was reprinted from the new First Principles page at Heritage.org. For more answers to frequently asked questions, visit http://www.heritage.org/Initiatives/First-Principles/basics.

Something to ponder- what is Seperation of Powers?
Each branch of the Government (Executive, Legislative, Judicial) is seperate, but equal. Each branch has its own responsibilties. In this instance the President can't tell the Senate it's not in session, just becuase he says so. Both Houses of Congress decided when to recess and when to be in session.
Something better to ponder .. when one part of the government is obstructing every other part, is that the best thing for our nation? The GOP (aka Tea Party) is trying to push policy toward a single end that is making our government impotent. So tiring!
You ask when one part of the government is obstructing every other part, is that the best thing for our nation? Not when the one part is unconstitutional and there shouldn't be another part. Be specific to your mention regarding the GOP trying to push policy and to what end? What are you talking about?