This is the act of transferring assets into public ownership. It usually refers to the transfer of private assets, but may also mean assets owned by other levels of government. The opposite of nationalization is called privatization. This process is distinguished from property redistribution in that in the former case, the government retains control of the property after acquisition. Wikipedia

In Venezuela, nationalizations started on the 1970's, when the government of president Carlos Andrés Pérez decided to create the oil company Petróleos de Venezuela, SA (PDVSA) and decreed the nationalization of Venezuela's crude oil reserves. But in the 1990's, government of president Rafael Caldera changed those policies and opened Venezuela upstream oil sector to private investments. It was the start of a series of privatizations that include power supply and telecom companies.

Nationalization - Oil Wells

But when Hugo Chavez sworn as President of, then, Republic of Venezuela in 1998, the shadow of nationalization took Venezuela again. Government of President Hugo Chavez has becoming stricter about managing Venezuela energy and telecom industry. In 2006, Chavez announced a series of new nationalization plans pointing these important industries in Venezuela as a part of promotion of his "Socialism of 21st Century".

Telecom:

Among with the nationalization of the energy and oil industry, Hugo Chavez also decided to buy the major Venezuela telecom company CANTV, who offers to venezuelans phone lines, Internet access and mobile services. Opposition groups inside and outside Venezuela are denouncing that Chavez gave CANTV to Cuban intelligence to spy people in Venezuela. In 2007 Chavez announced the construction of a big fiber optic cable that will connect Venezuela with Cuba, to bring telecom support to Cuba.

Chavez oil

Wikipedia: Energy Policy

PINR

Wikipedia: Hugo Chavez

Press TV

International Herald Tribune

Energy:

In Venezuela, the main electricity source is hydropower. Hydroelectricity production is concentrated on the Caroní River in Guayana Region. The largest power companies are state-owned CVG Electrificación del Caroní (EDELCA), a subsidiary of the mining company Corporación Venezolana de Guayana (CVG), and Companía Anonima de Administracion y Fomento Electrico (CADAFE) accounting respectively for approximately 63% and 18% of generating capacities. Other state-owned power companies are ENELBAR and ENELVEN-ENELCO (approximately 8% of capacities). The rest of the power production is owned by private companies. The largest private power company is Electricidad de Caracas (EDC), majority-owned by the US-based AES Corporation, (11% of capacities), which owns the majority of conventional thermal power plants. Wikipedia

But this was until 2007 when president Chavez decided to take 100% control of all the power companies. On February, the president Chavez signed an agreement to buy an 82.14% stake in Electricidad de Caracas from AES Corporation. Paul Hanrahan, president and CEO of AES said the deal has been a fair process that respected the rights of investors. The same occurred with SENECA who supplies power to Margarita Island residents.

CANTV

Oil Wells:

On May 1, 2007, Venezuela stripped the world's biggest oil companies of operational control over massive Orinoco Belt crude projects, a vital move in President Hugo Chavez's nationalization drive. Oil and Energy Minister of Venezuela, Rafael Ramirez told oil companies to give the state a greater share of profits, or they must get out from Venezuela. Whit this announce, foreign oil companies were forced to sign agreements giving majority control of hydrocarbons projects to PDVSA oil company. Projects owned by companies like ConocoPhillips, ExxonMobil, and Petro-Canada, who failed to sign these agreement, were took over by PDVSA.