Case Study worldwide spending on public cloud services reached $47.4 billion in 2013 and is expected to be more than $107 billion in 2017. Moreover, over the 2013–2017 forecast period, public cloud services have a compound annual growth rate (CAGR) of 23.5%, five times that of the IT industry as a whole[5]. Cloud computing certainly seems to be the phrase "du jour" in much of the computing world today, many experts now think that cloud computing will be "the next big thing"[6]. The promise of cloud computing is that, it can bring together practices, tools and technologies that will better position a public organisations to operate in a significantly more efficient, predictable, flexible, and accountable mannerCountries leading the way in cloud adoption in terms of Government institutions are USA, Japan, and United Kingdom[6].Theories about ICT innovation adoption The study of the diffusion of innovations has a multidisciplinary nature that involves various scientific fields (Rogers, 2003). According to AlQaisi (2009), two key disciplines, psychology and sociology, have had a great influence on the development of models and theories regarding ICT innovation adoption. These two disciplines emphasise technology acceptance behaviour, while the management of information and communication technology focuses on system features relative to technology acceptance. As a result, the adoption and diffusion of ICT innovations has become a heavily studied field. In reviewing ICT innovation adoption studies, it is noticeable that there are important challenges linked with the adoption of new technologies. In many studies have started to investigate the process related to this topic, spawning an extensive literature on the field (Jeyaraj et al., 2006; Korpelainen, 2011). Examples of these are the studies carried out by, for example, Kwon and Zmud, 1987; Moore and Benbasat, 1991; Thong, 1995; Premkumar, 2003a; Rogers, 2003; Ritchie and Brindley, 2005; Jeyaraj et al., 2006; Venkatesh et al., 2007. This extensive body of work that has surfaced on the adoption and the use of new ICT have made this research stream one of the richest and most mature in the information systems field (Venkatesh et al., 2003; Jasperson et al., 2005). Studies of innovation diffusion have focused on both individual and organization levels of analysis (Slappendel, 1996). Early literature on innovation diffusion was concerned with the acceptance of new ideas and innovations by independent individuals (Rogers, 2003). As early as in the late 50's developments in the field of innovation diffusion led to a growing interest in organizational innovation, i.e. innovation among organizations (March and Simon, 1958; Zaltman et al., 1973). The field of innovation in organizations was refreshed in the 1980s by the study of new communication technologies (Van De Ven and Rogers, 1988). Damanpour (Damanpour, 1992) argued that large enterprises are more likely to adopt innovation. Process innovation historically seemed to favour the large, bureaucratic organization (Porter, 1998). Researching ICT innovation adoption and diffusion in Public organization is different from studying adoption in large organizations. "Like any area of academic enquiry, the small organization is distinctive in the nature and kinds of research problems that it presents" (Beaver and Prince, 2004, p. 35). It is often the case that a theory developed for large orgnizations cannot be implemented in small-business (Thong et al. 1996). Small enterprises are not scaled-down versions of large enterprises (Welsh et al., 1982; Thong, 1999). Small orgnizations are not a homogeneous group; they are different and have special characteristics, objectives and qualities (Beaver and Prince, 2004). Small orgnizations often have structures that are simple, but highly centralised (Thong et al., 1996). Structural differences between small and large orgnizations stem from the different frameworks that orgnizations use to operate their business. The structural framework can differ based on the availability of (or substantially less sophisticated) information systems management (Kagan et al., 1990) and also based on the size and the industry in which the orgnizations operate. Previous studies on ICT deployment have shown that large orgnizations often use ICT infrastructures to harmonise and communicate across different organisational levels and divisions, and have been described as being willing to employ it in their daily operations more intensively; However, Public orgnization often use ICT for less formal communication (Wong and Sloan, 2004 ; Ramdani, 2008). Public orgnization tend to concentrate on basic functionalities, such as using electronic mail (e-mail), and also tend to focus on general applications (e.g. off-the shelf systems) to support specific organisational tasks such as administration and accounting (Wong and Sloan, 2004 ). This can be related to the levels of resource available, which are obviously greater in large orgnizations (Buonanno et al., 2005). Smaller orgnizations are more dynamic, innovative and responsive to market changes than large ones (Nolan and O'Donnell, 1991). Public orgnization are often seen as dynamic organizations that are supposed to easily adapt to modern ICT innovations. However, Lumpkin and Dess (Lumpkin and Dess, 2004) identified many reasons that may delay the adoption of ICT, such as a lack of awareness and knowledge. Although extensive empirical research has been conducted in the field of ICT innovation adoption and Public organization, there have been few studies that present a sufficient