# Sustainable Transformation: A Case Study of an Engineering-to-Order Additive Manufacturing Firm
## 1 Introduction  
Additive manufacturing (AM), commonly referred to as 3D printing, has been integral to industrial processes for over three decades [1, 2, 3]. While AM typically represents industrial-scale production, 3D printing is associated with low-cost home printers [4]. However, existing research highlights the unsustainable nature of AM practices [5, 6, 7], underscoring the lack of guidance for achieving sustainability within AM firms [8]. This challenge is particularly relevant for small- and medium-sized enterprises (SMEs), which lack practical guidelines for implementing sustainable measurement systems [9]. Studies reveal that despite investments in advanced equipment, AM companies often neglect process optimisation, resulting in high costs, energy consumption, and material waste [5, 10, 11, 12]. Moreover, this oversight contributes to increased reject rates and unsustainable post-processing, particularly in high-volume production settings [13, 14, 15]. The imperative for sustainability in AM operations is increasingly evident as more companies adopt AM for manufacturing, highlighting the need for its sustainability for societal and industrial advancement [6, 7, 16]. Recent years have witnessed AM companies reevaluating strategies for global sustainability and social well-being [17, 18, 19, 20], with numerous authors delving into AM sustainability [6, 21]. However, existing assessment techniques often fall short, lacking a comprehensive view of AM's economic, technical, and environmental dimensions [6]. This manuscript aims to bridge two critical gaps in the literature: the sustainability deficit in AM operations [5; 6; 9; 11; 22] and the absence of guidance on enhancing sustainability, particularly for SMEs [8]. The research questions are as follows:  
* Q1: How can the sustainability of AM operations be enhanced? * Q2: What tools are available to guide AM companies toward greater sustainability, providing a holistic view of AM operations? Furthermore, the research delves into the integration of lean philosophy, AM, and sustainability, highlighting the advantages of this synergy for AM companies. As part of this integration, a case study is conducted focusing on sustainable value stream mapping (Sus-VSM), which aims to minimise waste from environmental, economic, and societal perspectives, in alignment with the triple bottom line (TBL). This approach is novel given the scarcity of literature presenting a comprehensive approach to the entire production process for AM, such as the described multi-jet-fusion (MJF) process. Previous approaches often focused on specific elements of the production process or lacked an analysis of the entire process from order acceptance to product delivery [6; 23; 24; 25]. Additionally, this paper builds upon prior research [9; 26; 27; 28; 29; 30; 31] by exploring the integration of sustainability into the balanced scorecard (BSC) framework [32]. It introduces a fifth perspective, the \"Society and Environment\" perspective, which is designed to encompass both environmental and social aspects. This addition enables organisations to balance financial performance with sustainable development goals (SDGs), thereby aligning strategic objectives with broader societal and environmental responsibilities. The manuscript ultimately proposes a sustainability strategy map (SSM) to enhance the effective implementation of the BSC and to facilitate the achievement of strategic sustainability goals. This development builds on previous research demonstrating the efficiency of strategy maps in aligning corporate strategies with sustainability objectives [33; 34; 35]. The paper follows this structure: Section 2 provides the theoretical background, while Section 3 outlines the research methodology. In Section 4, the literature review is presented, and Section 5 presents the case study, including the analysis of the MJF production process using Sus-VSM for holistic evaluation. SSM is presented in Section 6, followed by discussion and conclusions in Section 7.