*3.2. Sampling and Data Collection*

This study employed a quantitative survey via the Fuzzy Delphi method. In obtaining expert opinions using the Fuzzy Delphi method, the ideal sample size is between 10 and 50 respondents [105,106]. Therefore, the authors decided to sample 40 smart city practitioners from the Kuala Lumpur Greater Valley area, including the city of Kuala Lumpur, Putrajaya, and Cyberjaya (Table 8).


**Table 8.** Informant sampling.

As Table 8 shows, this group of practitioners consisted of those in the government, private, and self-employed sectors. They represented the middle class and various professional job roles, such as director/CEO, assistant director/senior officer, executive officer, engineer/planner/architect, and technician. Since the 1970s, the middle class has emerged as a significant group contributing to the urbanization process in major cities in Malaysia [107]. Thus, the selection of professionals as respondents was significant given the composition of this group, the majority of whom lived in urban areas. The professionals were selected based on various criteria: they had to have a minimum of five-year work experience; possess at least a bachelor's degree; and be primarily involved in the planning, design, delivery, and management of cities and their development.

The success of the Fuzzy Delphi method depends on the insights and information supplied by experts. Thus, a panel of experts/respondents was identified through a purposive sampling and nomination process, rather than random selection. Later, a focus group discussion was organized, and data were collected.
