Management is an important aspect for organisation's effort to develop sustainability. To assess and understand the existing dimensions of sustainability, it is important to categorise it. Therefore, sustainability and its assessment become an essential component of corporate performance management (Saeed, Kersten, 2017). To assess sustainability, both qualitative and quantitative studies have been conducted in the last two decades (Schaltegger et al., 2016; Martınez et al., 2017).

Business processes in organisations can be categorised according to the importance of the core process for the organisation itself, with the processes being divided into three main parts: core processes, secondary processes, which are as important as the supporting processes, and managerial processes. Nowadays, the importance of supporting processes for the company's performance success is notable (Kaziliūnas, 2004, Strazdas, Černevičiūtė, 2014, Sobotkiewicz, 2015). One of the most important supporting processes is continuous improvement, which marks an important significance and progress for the company. However, despite the different analyses of business processes, we still have a gap in both academic literature and practice (Carvalho, Rabechini, 2011, Marcelino-Sadaba et al., 2015, Singh et al., 2012, Thomson et al., 2011).

Analyzing the existing scientific literature about sustainability, it can be noticed that social businesses using circular economy principles achieve cost savings, new forms of income, long-term competitiveness, resource conservation, customer interest, and attract new customers, etc. (Stratan, D., 2017). However, the lack of clear financial benefits of sustainable implementation is still a barrier to the diffusion of sustainable development, and these benefits will not be achieved until end-users fully support the implementation of the new concept (Støre-Valen, M., Buser, M., 2018). Research on corporate sustainability shows that companies focus on society and values, but unfortunately, this is not the only principle that can be considered as a hallmark of a sustainable company. The current scientific literature on sustainability focuses on the impact of firms and industries; there is a lack of broader knowledge and newer insights involving other systems (Whiteman et al., 2013, Bansal and Gao, 2006). Sustainability has also become a component of corporate ethics in response to perceived public dissatisfaction with the long-term damage caused by the focus on short-term profits (Grant, M., 2020).

The key factors for implementing sustainability are the company's philosophy, customer needs, personal interest, organisational culture, and top management support. Importantly, disclosure of sustainability through reporting is a key aspect of companies developing sustainability. Research shows that while companies recognise the importance of sustainability, a large proportion do not pay practical attention to sustainability management (Bonini et al., 2010). Even though social business can focus on social value creation, it remains one of the most difficult part of implementing sustainability in social business organizations. Due to the need to develop sustainability, sustainable social business models are emerging in the scientific literature, as the sustainability practices of existing businesses are insufficient. It is also pointed out that the two concepts of corporate sustainability and social business are closely related, but it is still debatable whether they can coexist (Grant, M., 2020).

The main problems of sustainability implementation are the cost of the measures and the difficulty of measuring social and environmental aspects due to their qualitative nature and the lack of support from leaders (Corsi, K., Arru, B., 2020). Results show that some of the main barriers to the implementation of sustainability practices are the lack of knowledge in organisations, lack of time, and lack of commitment from managers (Elmualim et al., 2012). Researchers underline that there still exist challenges in terms of collaboration between practitioners and users (Thomsen et al., 2013; Risholt et al., 2013; Moum et al., 2017; Shah, 2007; Then, 2013). Practitioners tend to focus on technical solutions and take it for granted that consumers will accept this and behave according to regulations (Johansson, 2017).

This implies that to develop sustainability more effectively, it is also necessary to analyse public attitudes towards sustainability. As organizations are dependent on the natural environment, the actions and activities of organizations affect the same environment and provide some feedback (Starik, Rands, 1995, Starik, Kanashiro, 2013). Therefore, it is important to acknowledge the need to examine existing boundaries and recognise the dependence of organisations on societal, economic, and environmental aspects (Meadows et al., 2009, Rockstrom et al., 2009, Marcus et al., 2010, Whiteman et al., 2013, Winn, Pogutz, 2013). Research shows that while companies recognise the importance of sustainability, a large proportion of companies do not notice practical attention to sustainability management (Bonini et al., 2010). In analysing the reasons for this, it is important to mention that the perception of the fundamentals of sustainability is unclear and the duration of the return on investment is still unknown (Naude, 2011). For achieving positive change, sustainability management should be one of the key processes for improving company performance. Also, low awareness of the importance of sustainability and thinking about the return of the individual company is one of the main obstacles to sustainable development. Therefore, the sustainability improvement cycle is defined as a kind of supporting process for the company's activities, as part of the organisational development process, in which evaluation becomes one of the main aspects and outcomes.

Since the process of improving performance is essential not only to achieve more efficient results but also to make more effective decisions for the benefit of society, sustainability management is becoming one of the key tools that can help to bring significant change. Figure 1 illustrates the sustainability management cycle of an organisation, which consists of four main parts: planning, implementation, assessment, and feedback. Assessment is one of the key aspects here. This means that companies should not only improve and adapt the sustainability management resources, but also dedicate time and resources to innovation and learning. This situation highlights the need to analyse sustainability not only from the company's perspective, but also from the perspective of its stakeholders.

Figure 1
Organization’s sustainability management cycle
Asif, Searcy, 2014

To better illustrate the aspects of the topic under consideration, it is important to understand that the establishment of sustainability measurement indicators (as criteria) is a very important part of an organisation's efforts to continuously develop sustainability.

The process of sustainability management is complex, involving a number of execution steps that are designed with a long-term perspective (Figure 2).

Figure 2.
Steps for continuous improvement of the sustainability development process
Asif, Searcy, 2013

Effective management of the sustainability development process requires deep knowledge of how we can achieve positive results. We still do not have a common approach to sustainable development and its management, but there is significant interest in this area. Certain stages of the process can be linked to a company's activity, but there is still a need for common evaluation criteria. However, it is clear that sustainability is about the long-term process to achieve effective change.

An important aspect of the analysis of consumer attitudes towards sustainability is that changes in public attitudes, e.g., positive attitudes towards sustainability, facilitate the development of sustainability, not only in organisations but also in society. Sustainability needs an enabling environment to evolve and move towards a more mature form of sustainability. Therefore, it is important to identify how consumers feel about sustainability and what indicators they consider to be indicative of the link between sustainability and appropriate outcomes and positive change. The research shows that sustainable businesses see themselves as operating as an organisation in community and that a company cannot be sustainable if community is not sustainable itself (Ketprapakorn, Kantabutra, 2019). Therefore, in this case, it is appropriate to analyse the inclination of consumers to assess sustainability, and the behaviour conditioned by it, to achieve an effective sustainability development.

The analysis of the scientific literature shows that there is not enough information on consumer intentions to purchase sustainable products or services. Research shows that changes in the environment are influencing consumer perceptions and that the concept of sustainability is becoming increasingly important to consumers (Bonini, Oppenheim, 2008). This indicates a favourable environment for the development of sustainability, as consumer attitudes are an important factor in the development of sustainability. Increased awareness and interest in sustainability is expected to influence consumer purchasing decisions (Paul, Modi, Patel, J., 2016, Azeiteiro et al. 2012) and the consumption of sustainable products can be one of the approaches to sustainability development that should be further explored not only in the academic literature, but also in practice (Ritter, Borchardt, Vaccaro, 2015, Mont, Plepys, 2008). Most importantly, sustainable products are produced according to sustainable development principles, a trend that is gaining popularity among consumers worldwide (Paul, Modi, Patel, 2016, Ritter et al., 2015, Lijuan, 2003). Therefore, it becomes important to analyse indicators that show the development of sustainability and to involve users to understand the main challenges and to achieve sustainability more effectively.

Consumers will buy sustainable products when their needs in terms of safety, quality, accessibility, and convenience are fulfilled. It is also important that consumers understand that buying sustainable products or services can help solve societal problems (Ottman, 1992). To advance sustainable development, it is necessary to increase knowledge about sustainability and its implications. Previous research shows that demographic characteristics (such as age and education) influence the purchasing behaviour of sustainable products. What is more, knowledge about sustainability is an important factor influencing the purchase of sustainable products (Franzen, Meyer, 2010, Sidique, Lupi, Joshi, 2010, Arslan, Yilmaz, Aksoy, 2012, Vega-Zamora, et al., 2013, Paul, Modi, Patel, 2016, Yadav, Pathak, Young, 2016). This situation shows that the only initiative of social business organisations is not enough - the involvement of society in sustainable development is also needed. The literature distinguishes the theory of reasoned action and the theory of planned behaviour (Fishbein, M., 1979, Ajzen, I., 1991). The main aspects of the theory are that consumer behaviour is influenced by intention, by attitudes towards a certain behaviour, by a subjective norm and by perceived behavioural control, which can also directly influence consumer behaviour. The analysis of consumer behaviour becomes very important when analysing the choice of sustainable products or companies. Nevertheless, consumer behaviour is considered to be one of the most complex areas of marketing (Hoppe, Marques Vieira, Dutra de Barcellos, 2013). It is important to understand that the intention to purchase sustainable products is related to the consumer's intention to purchase a product or service that is less harmful not only to the environment but also to society (Mohd Suki, 2016). Research shows that consumers' intention to purchase sustainable products or services is strongly influenced by positive attitudes and perceived value of sustainability (Rizwan, Ahmad, Mehboob, 2013, Vazifehdousta, 2013). Hence, knowledge about sustainability and its value plays an important role as it helps to create positive attitudes and appreciation of sustainability and create favourable conditions for sustainability to flourish.

Consumers who have knowledge about sustainability and sustainable products or services with positive past experiences have a high tendency to acquire strong intentions to continue purchasing sustainable products due to the positive impact of the environment (Lin, Chang, 2012, Norazah, 2013). Feelings and positive image are the main factors that create customer attitudes and influence their inclination to purchase sustainable products/services or choose sustainable companies (Schiffman, Wisenblit, 2014, Thogersen, et al, 2015). It is also important to mention that consumers with a deeper knowledge of sustainability have more positive attitudes towards the environment and the purchase of sustainable products or services. (Rokicka, 2002, Huang, Yang, Wang, 2014). The results show that to achieve sustainable development, it is necessary to analyse not only the ability of companies to act sustainably, but also the contribution of consumers to sustainability by analysing consumers' tendency to value sustainability and their purchasing behaviour related to it.