When the two parties are unable to reach consensus on the collective bargaining agreement, this is called
a bargaining impasse. Various kinds of strikes are used to show the displeasure of workers regarding a
bargaining impasse. An economic strike is a strike stemming from unhappiness about the economic
conditions during contract negotiations. For example, 45,000 Verizon workers rallied in the summer of
2011 when contract negotiations failed.  The two unions, Communications Workers of America and the
International Brotherhood of Electric Workers, claim that the new contract is unfair, as it asks Verizon
workers to contribute more to health plans, and the company is also looking to freeze pensions at the end
of the year and reduce sick time.  Verizon says the telecommunications business is changing, and it
cannot afford these expenses. An unfair labor practices strike can happen during negotiations. The goal of
an unfair labor practices strike is to get the organization to cease committing what the union believes
to be an unfair labor practice. A bargaining impasse could mean the union goes on strike or a lockout
occurs. The goal of a lockout, which prevents workers from working, is to put pressure on the union to
accept the contract. A lockout can only be legally conducted when the existing collective bargaining
agreement has expired and there is truly an impasse in contract negotiations. In summer 2011, the
National Basketball Association locked out players when the collective bargaining agreement expired,
jeopardizing the 2011–12 season  while putting pressure on the players to accept the agreement.
Similarly, the goal of a strike is to put pressure on the organization to accept the proposed contract.
Some organizations will impose a lockout if workers engage in slowdowns, an intentional reduction in
productivity. Some unions will engage in a slowdown instead of a strike, because the workers still earn
pay, while in a strike they do not. A sick-out is when members of a union call in sick, which may be illegal
since they are using allotted time, while a walk-out is an unannounced refusal to perform work.
However, this type of tactic may be illegal if the conduct is irresponsible or indefensible, according to a
judge. Jurisdictional strikes are used to put pressure on an employer to assign work to members of
one union versus another (if there are two unions within the same organization) or to put pressure on
management to recognize one union representation when it currently recognizes another. The goal of a
sick-out strike is to show the organization how unproductive the company would be if the workers did go
on strike. As mentioned under the Taft-Hartley Act, wildcat strikes are illegal, as they are not authorized
by the union and usually violate a collective bargaining agreement. Sympathy strikes are work
stoppages by other unions designed to show support for the union on strike. While they are not illegal,
they may violate the terms of the collective bargaining agreement.