||The developmental perspective is one of the elements taken into account in the development of marital relationships in the family development cycle as it explains the process of transformation encountered by the lasting marriage couples chronologically, before marriage to ageing. Therefore, this study is inspired to explore the process of marital relationships development, the developmental tasks and challenges endured by the lasting marriage couples in the family development cycle through three research. questions. These questions are (I) What is the marital relationship development process of the lasting marriage couples in the family development cycle? (ii) How do the developmental tasks of the lasting marriage couples remain in each phase of development? and (iii) What challenges do the lasting
marriage couples faced during each phase of development? In addition to answer every question, the researcher employs qualitative research through hermeneutic phenomenology design. The researcher applies the purposive sampling method. This research involves 12 urban and rural couples that fulfilled the criteria. The researcher used three data sources which includes in-depth interviews, observations and
documents analysis. The data were analysed through the hermeneutic circle method and analyzed thematically using the Nvivo Plus 12 application. Overall, the study found 179 themes explaining the developmental process of marriage relationships, developmental tasks and strategies of achievement and also challenges facing married couples in the chronology of the development in marriage relationship in the family development cycle. This study proposes four phases of the development in marital relationships development in the family development cycle, namely (i) the premarital development phase; (ii) the early developmental phase of the marriage; (iii) the mid-marriage development phase; and (iv) the developmental phase of lasting
marriage. The four stages of the development incorporate eight transitional elements, ten roles and 22 marital relationship goals. Besides that, there are a total of 22 developmental tasks undergone by the lasting marriage couples in all four phases of development. The developmental task is a responsibility that must be fulfilled in marriage. In this research, the task of sustaining a marital relationship is one of the
most critical responsibilities couples do in every phases other than parenting duties and relationships with others, such as in-laws and communities. Implementation of development tasks involves 96 strategies. The main strategy used by couples to carry out duties of development involves elements of religion, love and affection and
responsibility. Lasting marriage couples also undergone 21 challenges according to the chronology of the developmental phase of the marriage relationship. The most common challenges faced by couples throughout the marriage are third-party intervention, financial and an unexpected event. Furthermore, the dyadic coping, which involves the cooperation of the couple in their marriage reflects the couples'
success through each phase of development. Hence, the outcomes of the research develop the conceptual model of the development of marital relationships in the family cycle, as a reference and guide in the field of marriage and family research. This study also proposes significant suggestions in developing future lasting marriage relationship research.