LONDON (Reuters) - Few organizations have moved to cloud computing -- the delivery of computing as a service from remote centers -- and of those that have, many are disappointed with the results, a survey published on Tuesday found.

Fewer than one in five organizations questioned have outsourced the hosting of their applications to cloud computing providers, with two-thirds in early discussions, in trials or not considering a move, said computer security firm Symantec.

Many firms are looking at cloud computing providers such as Amazon, Microsoft, Salesforce, Google or Rackspace to help them increase their scale without installing expensive hardware and software locally.

IT research firm Forrester has forecast that the global cloud computing market will grow from $41 billion this year to $241 billion in 2020.

While three out of four organizations have adopted or are currently adopting cloud services such as backup, storage and security, when it comes to the wholesale outsourcing of applications there is more talk than action, Symantec found.

Concerns about security and a lack of expertise among IT staff are the main factors holding companies back, according to the survey of 5,300 organizations carried out by Symantec, which makes the popular Norton anti-virus software.

"While computing changes constantly, most shifts are simple changes that don't require organizations to change the core of how they work. Not so with cloud computing," Symantec said. "It requires organizations to change how they approach IT."

Symantec found that security was the number-one concern of organizations mulling a move to the cloud, with more than half of respondents worried about malware outbreaks, hackers stealing their data and insiders sharing sensitive information.

But the majority of respondents also said they expected that implementing cloud computing would eventually improve or at least not affect their security.

Symantec said the immaturity of the market meant there was a big gap between the expectations and actual results of those who had implemented cloud technologies, in areas like IT agility, disaster recovery, efficiency, costs and security.

Symantec spoke to organizations of all sizes in 38 countries in its telephone survey carried out between April and June 2011.

(Reporting by Georgina Prodhan; Editing by Helen Massy-Beresford)

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