Containerisation is making the world smaller since cargoes can go to most corners of the earth without incurring high freight cost (including transshipment cost). Thus, containerisation, together with custom tariff reduction, has contributed to phenomenal increases in world international trade volume during the past four decades. In ocean shipping/transportation networks, ports are nodes where cargoes can be stored, processed, and transferred. How to scientifically choose a port of call, especially a transshipment port of call, is always a great challenge to shipping management. At the same time, major port service providers (including port authorities, port operators) are keen to know what their customers' (i. e. ocean container carriers') main requirements are and what they really demand from them, since their customers' requirements appear endless their resources are limited. There is always a trade-off relationship between the cost and service quality in major container transshipment port services. How to find ocean container carriers' port of call selection determinants is thus very important and urgent from the port service providers' viewpoint. This research employed a two stage survey, a pilot survey carried out in Taiwan and a global survey carried out by post in the UK, to quantitatively determine the most influential service attributes for three container ports in Taiwan/six leading container ports worldwide, respectively, by eliciting their importance as perceived by their key customers (i. e. global ocean container carriers). Containers' terminal handling cost was globally recognised as the most important service attribute influencing global ocean container carriers' transshipment port selection decision, probably due to the increasing homogenisation of major transshipment ports' service quality. One of the two mechanisms Porter (2004) suggests to create value for their buyers is by lowering buyer cost. This mechanism was perceived important by both OCCs and PSPS. The second mechanism recommended by Porter (2004) is raising buyer performance which was found very difficult because of the increasing homogeneity of sellers' service quality. In summary, survey results indicated no major perception gaps regarding the importance of port service attributes between leading PSPs and global OCCs, suggesting buyers' and sellers' perception of value is the same in the container port service industry.