The current social climate in which sustainable awareness is prioritized, is affecting the port sector. In new-to-develop ports and in the expansion and maintenance of existing ports, implementing sustainability is encouraged.However, applying sustainability is not self-evident. In order to achieve sustainability targets and to comply with the environmental laws, port authorities should be able to define and quantify sustainability. This research aims to define, quantify and improve sustainability in quay wall development, which is a most common infrastructure component in port development. The first step of this research is to develop a framework to assess port infrastructure on its sustainability performance. Following the Frame of Reference method (van Koningsveld & Mulder, 2004), the Framework ofSustainable Port Infrastructure (FoSPI) has been developed. The FoSPI consists of fourteen aspects of sustainability that has been derived from literature, which can be applied to all port infrastructure assets. Each aspect includes one of more targets that are determined by the company and/or by the location’s regulations. Furthermore each of these targets requires their own quantification tool, reference base, intervention measures and evaluation procedure. These are dependent on the location and the type of port infrastructure asset. If the target(s) is (are) achieved, this would mean that the infrastructure has reached a more sustainable level on this aspect. All fourteen aspects should meet their target(s) to conclude that the infrastructure has reached a more sustainable level. The FoSPI has been applied to quay wall development in the Port of Rotterdam(PoR) and this resulted that only four out of fourteen can be specified to be further assessed. The remaining eleven aspects should be investigated further to assess quay wall development in total. As the PoR has prioritizedGreenhouse Gas (GHG) emissions (this was based on literature and interviews within the port), this thesis will focus on the the GHG emissions of the aspect ’Air pollutants’ in quay wall development. Nevertheless, theway this GHG target was included in the analysis can also be used for other sustainability aspects for which the company has a target.The second step of the research is to determine the actual value of GHG emission of a current quay wall project. To do this, an evaluation procedure and quantification tool was selected. The author proposed to quantify a 100meter standard short sea quay wall of the PoR with a life time of 100 years as the reference base case. A tool is selected that is able to quantify GHG emission, is objective and represents actual quay wall development. Usingliterature sources, the tool DuboCalc is proposed, because it is based on the life cycle analysis, is sector specific and is simplified (compared to other tools). However, the tool should be handled with a certain caution. The research showed that the results are not 100 % reproducible. However, when a thorough check and evaluation is part of the process, the results will converge. In the research, the results of the exercise had a percentage relative range of 28 %, but after a thorough check and evaluation, the second results achieved a range of 8 %.Secondly, DuboCalc doesn’t include all quay wall objects, hence it will give an approximately GHG emission. The tool has room for improvements. The tool is used to quantify the reference base by using an actual PoR project, the HHTT terminal as the case study. This resulted in a total emission of 1.9 kt of CO2-eq for a 100 meter standard PoR short sea quay wall with a life time of 100 years.The third step of this research is to determine how the PoR can reach their GHG targets. The reduction measures to achieve the target of being climate neutrality in 2050, are discussed. A summation of suitable measures from multiple reports of PoR is made. Using literature, DuboCalc data and the case study, the most suitable measures were quantified for the PoR. It is concluded that the PoR should focus on the largest contributors of GHG emission. The following actions are advised: As from 2020, renewable energy could be used for the Impressed Current Cathodic Protection (ICCP) which could lead to 15% reduction in GHG emissions over the quay wall’s life cycle. The transition from fossil electricity to renewable electricity is without extra investment costs. Secondly, using renewable energy instead of diesel for the temporary drainage systems will reduce the emission with 14 %. Including previous actions a total reduction of 29 % is achieved. The costs of the amount of renewable electricity is lower than the required amount of diesel. Thirdly, if the PoR will invest approx. 170 euro for every saved CO2-eq, Hydrotreated Vegetable Oil (HVO) can be used as an alternative fuel for dredging to reduce emission with 8 %. Including previousactions a total reduction of 37 % is achieved. Further research could be done in alternative designs. This could lead to a reduction in concrete and steeluse, as they are the larger contributors. Alternative designs includes quay walls made out of Recycled High Density PolyEthylene (RE-HDPE), smaller dimensions of steel piles and prefab concrete quay walls with geo-polymer-based-cements.The evaluation procedure in which the quay wall is monitored every five years, could be implemented. This will help to evaluate the applied intervention measures and to oversee if the targets are going to be achieved. It will be part of the strategical planning of the PoR. Furthermore, the PoR could encourage the constructors to use electrified transport (on commercial scale available around 2025) and machinery (on commercial scale available around 2030) to reduce emission with 3 % and 11 % respectively. Including previous actions a total reduction of 51 % is achieved. Finally, anticipating long term technical innovation in concrete with Carbon Capture and Storage (CCS) (on commercial scale available around 2030), hydrogen as dredging fuel (on commercial scale available around 2050) and steel with hydrogen as reduction-agent (on commercial scale available around 2050). This could reduce emission with 9%, 10 % and 24 % respectively. Including previous actions, except use of HVO, a total reduction of 86 % is achieved. Although the calculated reduction of GHG emission in 2050 does not satisfy the target of being climate neutral, the potential reduction of 86 % is a considerable improvement. For the PoR case, the described three-step approach has led to an improved insight in sustainability of quay wall development, and to specific recommendations to reduce the GHG emission.The method is applied to quay walls and to the PoR, but it can be applied generally as well, provided that the targets are adapted to the concerned company and its location, and the quantification tool, the reference base and the intervention measures are adapted to the type of asset and the location.The research does contain various limitations, namely only one target of one aspect could have been investigated in depth, although the influence of the proposed solutions on the other aspects is not considered. It is recommended that this influence should be determined to see if the targets of other aspects of sustainability are met as well.