2.1. The Resource-Based View and the Ability–Motivation–Opportunity (AMO) Theory
For this research, the hypotheses have been developed by merging two principal theories in the field, namely the Resource-Based View (RBV) theory proposed by Barney [
23] and the Ability–Motivation–Opportunity (AMO) theory initiated by Bailey [
24], as described by Marin-Garcia and Tomas [
25], to test how leadership and human resources practices might be a vital resource for leveraging GSC practices and influence positively sustainable performance in the context of the pharmaceutical industry in the KSA. The resource-based view (RBV) is a management theory that focuses on a firm’s internal resources and capabilities as key determinants of its competitive advantage and superior performance. According to the RBV, if a company possesses unique, valuable, and difficult-to-replicate resources, it can achieve sustained competitive advantage over its rivals. This theory suggests that a firm’s internal capabilities and resources, such as technology, skilled workforce, and proprietary knowledge, contribute significantly to its long-term success in the marketplace [
23].
By applying the RBV, transformational leadership can transform employees and managers into valuable resources and make the human resource management function adopt green practices that help develop, motivate, and provide opportunities to exhibit green behaviours regarding SC practices, as well as achieve a sustainable competitive advantage and superior performance. In parallel with the RBV, the AMO theory is helpful in comprehending how leaders and HR managers can encourage environmentally friendly behaviours and practices in supply chain management. It also explores the connection between HR management and performance, one which suggests that employee skills, motivations, and contributions are essential for sustained performance. This perspective provides an integrated comprehension of how leaders and strategic human resource management managers contribute to organizational performance [
26].
As per the AMO theory, HRM practices provide an overarching architecture, influencing (1) employee ability, such as recruitment and selection, training, and development; (2) motivation, such as rewards, incentives, employee empowerment, and compensation; and finally, (3) opportunity, such as teamwork, and empowerment to contribute to the firm’s sustainable performance [
27]. Through the application of AMO theory, this study expects that pharmaceutical companies’ leaders will encourage green HR management and employees’ ability, motivation, and opportunity to behave according to environmental management goals and objectives through the green process [
28], including the GSCM process.
2.2. Green TL and Green HRM
There is a consensus among practitioners and researchers about the vital role of leadership in achieving higher performance. However, the mechanism that links leadership and performance is still unclear and unresolved. In other words, the leadership type can achieve superior performance in different ways [
29,
30]. GTL could be defined as a style of leadership that inspires and motivates the workforce to meet the organisation’s environmental goals while simultaneously supporting their developmental needs [
31]. GTL encourages staff members to learn new information and acquire new knowledge [
32], and in addition, gets them involved in green process- and product innovation-related activities so that the company can bring green products and services to the market and enhance the company’s environmental performance [
33]. Leadership is considered a crucial resource in the organisation’s green management, including using the RBV as a guide. Transformational executives have a distinct vision for a company’s present and future courses of action in the face of competitive marketplaces [
34]. As per Zhu et al. [
35], transformational leadership encourages better commitment, motivation, trust, and cohesion [
35]. The studies of Jia et al. [
18] show that intellectually motivated transformational leadership positively affects performance management, talent management, and workforce productivity. GTL embodies the principals and core values of the top management, which has a significant impact on the company’s GHRM [
18]. To put it another way, GTL’s emphasis on taking each employee’s needs into account may motivate them to create and implement GHRM practices to maintain their followers’ motivation and empowerment. We anticipate that GTL will support effective GHRM procedures like recruitment and selection, training and learning, performance assessment and management, and remuneration and incentive systems to a greater extent. This inspires, stimulates, and motivates followers to accomplish organisational goals [
35]. We suggest that using the AMO theory, GTL uses GHRM to enhance followers’ capabilities and skills and furnish opportunities for them to participate in environmental management-related activities for green innovations and ecological performance [
36,
37]. GTL influences GHRM practices through several key mechanisms: First, green transformational leaders communicate the importance of integrating green practices into HRM strategies, fostering a sense of purpose and alignment among employees in moving towards sustainability goals. They inspire and motivate employees to embrace green initiatives by fostering supportive and empowering work environments. They encourage innovation, creativity, and risk-taking in implementing environmentally friendly HRM practices such as green training programs, performance evaluations, and recruitment strategies. GT leaders can be considered as models in demonstrating their commitment to sustainability through their actions and decisions. Their personal dedication to environmental stewardship sets a positive precedent for employees to follow, influencing the adoption of GHRM practices throughout the organization. Finally, green transformational leaders empower employees to participate actively in green initiatives by providing opportunities for involvement, feedback, and collaboration. They create platforms for employee engagement in decision-making processes related to environmental sustainability, fostering a sense of ownership and responsibility among staff towards green HRM practices [
19,
30,
38,
39]. Therefore, we posit that:
H1a. Green transformational leadership positively relates to green human resource management practices.
2.3. Green HRM and Green SCM
GHRM refers to green recruiting and training and the development of green-practices-based performance appraisals, compensation strategies, etc. The adoption of environmental criteria for recruitment, such as personal orientation and environmental competences, are referred to as “green selection and recruitment”. The development of green competencies, which enhances organisational performance and capacity and emphasises the importance of the organisation’s commitment to green concerns and employee involvement in green processes, is referred to as “green training and involvement”, an aspect which gives employees the chance to participate in internal discussions about environmental development. Green performance management and compensation refers to the development of a system for tracking and rewards in order to encourage staff to practice ecological management [
40].
Previous research has shown the existence of multiple typologies for Green SCM practices. For instance, Zhu et al. [
41] presented a progressive-level-based model of GSCM deployment, starting with basic practices such as green sourcing, and extending to greening the entirety of intra- and inter-organizational processes; this view extends from the suppliers and their contribution, to the product design phase, the transformation phase, and the stage of delivering final products to customers and ensuring reverse logistics. The study emphasised the importance of following GSCM dimensions: intra-organizational environmental practices, green sourcing, green customer relationship management, ecological design, and finally, practices related to the recovery or regeneration of environmental and social capital. This involves making SC investments in eco-friendly or socially responsible practices contributing to long-term well-being and resilience. Prior GSCM empirical investigations have examined these five dimensions in great detail (e.g., [
42,
43,
44]). From a structural perspective, Huo et al. [
45] presented three groups of GSCM practises, categorised according to the sequence of flows from suppliers to customers. According to the researchers, a firm must integrate green issues into their relationships with customers and suppliers as well as integrate these issues into its internal processes. In the same context, and from a functional perspective, Hervani et al. [
46] recommended that green issues should be present in all functions, namely, sourcing, inventory management, production, transportation, distribution, and after-sales services. From a hybrid perspective, Rizki and Augustine [
47] counted ten green SC practices: green sourcing, green production, green marketing, green distribution, environmental design, internal environmental management, instruction on the environment, customer relationship management, green information, and green communication technology. Basing their approach on a process view, Zaid et al. [
48] adopted two main categories of green SCM practices: (1) internal green SCM, which comprises internal ecological design and management; and (2) external green SCM activities, which include reverse SC, environmental collaboration, and green sourcing. After putting all of the earlier theories up against one another in light of this research, four primary practices are obtained for the current study: (1) green production, maintenance, and inventory management, which refer to internal operations of SCM (INTO); (2) all marketing, distribution, and post-purchase services, which are included in the definition of customer relationship management (CRM); (3) green purchasing, transportation, and other associated processes, which are collectively referred to as supplier relationship management (SRM); and (4) ecological and environmental design (ECOD).
The contribution of GHRM to enhanced GSCM has garnered the interest of scholars and practitioners. The literature has confirmed GHRM’s role in acting on and emphasizing green supply chain practices, helping to enhance sustainable performance [
48]. GHRM practices impact how successfully the SC and business operate, as claimed by Albahussain et al. [
49]. The results of this study demonstrate that human resource practices affect SCP and, consequently, business performance. The results show that SCP may mediate between HRM practices and business performance in Saudi Arabian firms. As per Muafi and Kusumawati [
50], GHRM positively affects supply chain organisational learning (SCOL) and SCP. The SCOL has a significant positive effects on SCP and business processes. Furthermore, SC organisational learning mediates the relationship between GHRM and SC performance. Also, SC organisational learning mediates the relationship between GHRM and business processes. The mechanism through which GHRM and GSCM affect financial and environmental performance may be better understood by looking at their relationship. They focus on the mediating roles that effective SCM methods, practices, and outcomes play in the relationship between human resource management and performance. This fact has been concentrated upon by a growing number of conceptual contributions and practical studies in the field of human resource management (e.g., [
51,
52]). Jabbour and Jabbour [
53] have urged empirical research into the HRM–SCM mediation link, particularly as to environmental challenges. Previous empirical studies that looked into this connection revealed that some GHRM practices lead to the adoption of GSCM [
54,
55]. Actually, in the absence of GHRM practices, employees who are environmentally competent, motivated, and engaged would be lacking, and the adoption of GSCM practices would be hindered by challenges related to classical organisational culture and change management [
40,
53,
56].
Drawing upon RBV theory, it has been demonstrated that GHRM influence positively affects the firm’s performance through transforming the staff at all levels into valuable, rare, inimitable, and organised resources that provide the firm with an effective control of intraorganizational and inter-organizational processes within the SC network, and therefore a sustainable competitive advantage [
40]. By utilising this viewpoint in the context of environmental management, GHRM may have a vital role in fostering environmental beliefs and values to aid in developing a staff who are environmentally savvy and dedicated and who integrate ecological concepts into SC operations [
55,
57,
58]. Also, Ellinger and Ellinger [
59] and Jabbour and Jabbour [
53] emphasised that the GHRM concepts and practices strongly support the implementation of SC practices.
According to [
40,
48,
53,
58], GHRM influences GSCM through various key mechanisms as follows: GHRM enhances employee engagement and commitment. In other words, GHRM practices, such as training and development programs focusing on sustainability, environmental awareness, and green initiatives, enhance employees’ understanding of and commitment to environmental goals. Engaged and committed employees are more likely to align their actions with green objectives, including those related to the supply chain. Also, GHRM systems incorporate environmental performance metrics and incentives to encourage employees and suppliers to meet sustainability targets. By linking performance evaluations and rewards to green objectives, organizations incentivise behaviours that contribute to environmentally friendly supply chain practices. GHRM provides training and capacity-building opportunities to employees and suppliers on green technologies, practices, and regulations relevant to supply chain operations. By enhancing the skills and knowledge of stakeholders, organizations can improve the implementation of green initiatives across the supply chain. GHRM initiatives drive organizational culture change towards sustainability, influencing attitudes, norms, and behaviours related to environmental stewardship. A culture that values sustainability encourages innovation and adaptation in supply chain processes to minimise environmental impact. GHRM fosters open communication and collaboration among employees, departments, and supply chain partners on sustainability issues. Effective communication channels facilitate the exchange of ideas, best practices, and feedback, enabling continuous improvement in green supply chain management.
Based on the above discussion, it is suggested that the GHRM package of practices positively influences the implementation of GSCM practices. The hypotheses are developed below, and the theoretical model is depicted in
Figure 1.
H2a. GHRM practices are significantly and positively related to SRM.
H2b. GHRM practices are significantly and positively related to internal SCM.
H2c. GHRM practices are significantly and positively related to eco-design.
H2d. GHRM practices are significantly and positively related to CRM.
In today’s organisational dynamics, green transformational leadership (GTL) can significantly shape the environmental orientation of a company. However, realising and implementing green supply chain management (GSCM) practices often involve multifaceted processes. Herein lies the potential mediating role of green human resource management (GHRM), which aligns human resource practices with environmentally conscious values and acts as a conduit that channels and translates visionary green leadership into tangible green practices within the supply chain [
38]. By fostering an environmentally aware, motivated, and empowered workforce, GHRM bridges the gap between GTL’s vision and the actualisation of sustainable and eco-friendly supply-chain practices. This mediation is crucial in ensuring that the green principles advocated by leadership are seamlessly integrated into the organisational fabric, ultimately contributing to a more sustainable and environmentally responsible business model [
39]. Based on this discussion, the hypotheses dealing with the mediation role of GHRM are formulated as follows:
H3a. GHRM significantly and positively moderates the relationship between GTL and SRM.
H3b. GHRM significantly and positively moderates the relationship between GTL and internal SCM.
H3c. GHRM significantly and positively moderates the relationship between GTL and eco-design.
H3d. GHRM significantly and positively moderates the relationship between GTL and CRM.
From
Figure 1 above, in examining the direct impact of GTL on GHRM, it is evident that GTL plays a pivotal role in fostering environmentally conscious practices within organizational human resource management. Through inspirational motivation, idealised influence, individualised consideration, and intellectual stimulation, GTL cultivates a culture of environmental awareness and responsibility among employees. This directly influences the integration of green practices into human resource management processes, such as recruitment, training, performance appraisal, and rewards systems, thereby enhancing overall environmental sustainability efforts within the organization. Furthermore, the indirect effect of GTL on GSCM practices, including SRM, CRM, INTO, and ECOD, mediated through GHRM, underscores the importance of leadership in shaping the broader sustainability initiatives of the organization. By influencing GHRM practices, GTL indirectly impacts the adoption and implementation of green practices throughout the supply chain, facilitating collaborations with suppliers and customers, optimizing internal processes, and designing environmentally friendly products and services. This holistic approach underscores the vital role of leadership in driving sustainable practices across organizational boundaries.