This paper presents the development of a collapsible 15-l water fountain bottle made of an alternative material, PET, instead of a traditional refillable-type bottle made of polycarbonate. This bottle design offers several advantages including light-weight, use-and-throw concept and recyclability. The paper details the process and results of design, analysis and optimisation of the bottle shape using Pro/Engineer Parametric Modelling software and Pro/Mechanica Finite Element Modelling software. Some of the main criteria used in the design and development of this collapsible bottle include: light-weight, collapsibility, identical neck dimensions to fit standard size water coolers and manufacturing by one-step injection stretch blow-moulding process. Results are supported by analysis and pictures of the final designed bottle.