Over the past decades, workforce is rapidly becoming more diverse locally and globally. Actually, diversity is demonstrated by culture, gender, race and life-style as well as by employee needs and expectations. Furthermore, companies are realizing that people are one of the most valuable assets that the employees represent a competitive advantage which directly contributes to improve strategic HR objectives including well-motivated employees, attracting and retaining the qualified workforce and achieving a safe and productive workplace for them. Overall, an effective diversity of workforce is one of the most important key components which improve access and strong relationship in the fast growing markets as well as continuous improvement in the organizations.
Generally, researchers organize diversity characteristics into four areas: personality (skills and abilities), internal (gender, race, ethnicity, I.Q., sexual orientation), external (nationality, religion, marital or parental status), and organizational (position, department, union/non-union) (Digh, 1998a; Johnson, 2003; Simmons-Welburn, 1999).
Workforce diversity and its concepts
This diversity directly reflects in the workplace due to mixed workforce with different experiences and skills. The concept of diversity has two perspectives: narrow range diversity and broad-based diversity. Narrow range diversity describes a strong expressiveness on race and gender, and reflects in the workforce by demographic projections. Consequently, the companies that use this type of diversity management strive to recruit, promote, retain, and reward female and minority workforce. However, many critics uphold that using narrow range diversity would result in an imperfect transformation of organizational culture. Broad-based diversity describes a less visible diversity: personality, religion, education, background, specialty, and values. Usually, this diversity management exceeds differentiations of rice and gender and those companies which use broad definition are much more effective and suitable than its narrow-range definition. Because broad-based diversity recruit, retain, reward, and promote not only female and minority but also people of color, white which could be describes as heterogeneous mix of productive. For instance, the Vice-President of Apple Computer Kevin Sullivan maintains that diversity concepts should be introduced as "business, not social work" for effective implementation (Ivancevich & Gilbert, 2000). Another example one study compared 76 organisations US which classified as poorly minority-friendly (broad-based diversity) as a result, the minority-friendly organisations achieved higher than average performance in terms of return on investment, return on sales and return on equity (Von Bergen et al, 2005). At the same time, on 140 leading private and public organisations in UK found out that 80% of companies which use minority practices (narrow-range diversity) reported better business performance in terms of improved productivity, better service delivery and cost savings (Rutherford and Ollerearnshaw, 2002).
The heterogeneous composition of the workforce
Nowadays organisations know that without a diverse workforce and effective diversity management ability, organizational efficiency is under the threat of failure, being effectual at retaining, recruiting, and managing a diverse workforce helps and increases organizational productivity, bring access to new segments of the market, and improve business process. Basically, it is the way to success for business (Hubbard, 2003). As mentioned above, race, gender dimensions, religion and etc are can't fully manage diversity process. Another main trend in the diversity mix is homogeneous and heterogeneous workforce (Howland, J. 2001).
Table1 describes the diversity between two trends. Some studies show that several decades ago almost all organizations created homogeneous workforce did not make any connections between a diverse workplace. But today all of them find out a strong connection between workforce diversity. As a result of significant changes from homogeneous to heterogeneous workforce composition (increasing percentage of workers aged 35 to 55, a new entrants on the workforce are women, decreasing number of white and increasing number of people of color, equal balance of women and men), most companies increase their performance & profitably. Furthermore, demographical and cultural diversity management maximizes employees potential and equal opportunities (Monks, K., 2007).
Business diversity levels
According to Gandz (2001) case studies, the business is allocated into three diversity levels: service, design, and strategic which contribute to the strategic objective of HRM.
The service diversity level could be used by organizations to better serve and understand customer's needs due to globalization is bringing variety categories of customers to the market and requires from workforce with multitude backgrounds to meet the needs of such customers.
The design diversity level contains operational groups, management, and, marketing, which forces the companies to focus on designing products for a broad range of customers with vibrant cultures.
The strategic diversity level could be describes as the highest level of business and mostly concentrates on strategic thinking, knowledge and background of employees to create sagacious marketing practices for specific cultural groups.
Managing Diversity and HRM practises
Human resource management practices and workforce diversity managing diversity earns establishing a heterogeneous workforce to perform to its potential in an equitable work environment where no member or group of members has an advantage or a disadvantage (Torres, C.; Bruxelles, M., 1992). Managing diversity includes a process of creation and maintenance of environment which allows all people to reach the full potential in prosecution of the organizational objectives. After successful integration of diversity into human resource functions, diversity management tries to build certain skills, create a policy and practices which helps to get best workforce performance, effectiveness and competitive advantage (Maxwell, G. A., Blair, S., & McDougall, M. 2001). Furthermore, the effective diversity management always researches on people with variety cultures, backgrounds, and experiences who can bring new ideas to the workplace. Because most researchers indicate that, "best HR practices" at the recruitment and selection area could be positive influence on the organization's growth. But effective management of workforce diversity focuses on not just recruiting diverse but also retaining employees. By providing adequate training and development programs increases opportunities and privileges of the employees which could be easy way of increasing retention rates in the organization.
Diversity enhances marketability both domestic and foreign markets. Because of increasingly interdependence of the companies, diversity is needed at every level of their business in order to meet the demands and needs of the customers, employees, suppliers, and the community. Reviews of studies across large number of companies is identified both negative and positive results at diverse workforces. Generally, poor implementation of the diversity and poor practices could be reason for negative results. Although positive results at diverse workforce is explained as being due to reasonably high proportions of diverse workforce at all levels (workplace culture, leadership, communication, training, measurement and accountability) of the organizations.