Priorities for museums are changing. The mission of the new museology is to convert museums into places of enjoyment and learning, bringing their financial management into line with the social enterprises competing with the entertainment industry.

As time goes by, museums need to establish and apply the criteria necessary for their survival, paving the way for other public institutions to open up in their attempt to communicate and spread their heritage.

We can already see some commonly accepted conclusions about visitors' behaviour, which can help plan future exhibits that present learning as a constructive process, collections as objects that bring meaning, and exhibits themselves as communication media that should transform the way spectators think, serving as the message itself.

Internet seems to represent an effective medium to reach these objectives, as it capable of: a) adapting to the interests and intellectual characteristics of a diverse audience; b) rediscovering objects' meanings and offering sociocultural recognition of their value through its interactive potential, and c) employing attractive and stimulating elements for everybody's enjoyment.

With this in mind, we have to ask ourselves: What criteria should a virtual museum respect in order to optimise the diffusion of its heritage? What elements stimulate users to stay on a web page and have satisfactory virtual visits? What role does the application's usability play in all of this?