To apply semiotics to organizational analysis and information systems design, it is essential to unite two basic concepts: the sign and the norm. A sign is anything that stands for something else for some community. A norm is a generalized disposition to the world shared by members of a community. When its condition is met, a norm generates a propositional attitude which may, but not necessarily will, affect the subject's behaviour. Norms reflect regularities in the behaviour of members in an organization, allowing them to coordinate their actions. Organized behaviour is norm-governed behaviour. Signs trigger the norms leading to more signs being produced. Both signs and norms lend themselves to empirical study. The focus in this paper is on the properties of norms since those for signs are relatively well known. The paper discusses a number of different taxonomies of norms: formal, informal, technical; evaluative, perceptual, behavioural, cognitive; structure, action; substantive, communication and control. A semiotic analysis of information systems is adduced in this paper from the social, pragmatic, semantic, syntactic, empiric and physical perspectives. The paper finally presents a semiotic approach to information systems design, by discussing the method of information modelling and systems architecture. This approach shows advantages over other traditional ones in a higher degree of separation of knowledge, and hence in the consistency, integrity and maintainability of systems.