The discovery of suitable web services is a demanding challenge for organisations that plan to benefit from this technology. Strategic objectives, organisational structures, business processes and technology placed in a climate of constant change impact the normative behavioural patterns of people working in all kinds of organisations. Such dynamic conditions can have a profound influence over the discovery of appropriate web services. Advocated in this paper is a semiotic approach to web service description that configures a solution to take into account the dynamic conditions affecting web service discovery. The semiotic approach merges the articulation of dynamic conditions with web service description whilst facilitating the engagement of service providers and consumers in joint actions. Framed by affordance, joint actions capture the changeable normative behavioural patterns of people so that web service utilisation can be harmonised with organisational contexts.