The present chapter analyses the post-bureaucratic phenomenon, adopting a socio-cultural perspective and post-modern approach. According to the theoretical perspective proposed in this chapter, organizational systems should be considered a specific type of socio - cultural system. The apparent paradox of the dual nature of organizational systems, that may be conceived at the same time as autonomous and as interconnected socio-cultural realities, offers an extraordinary conceptual and methodological challenge for organization studies. The duality of complex organizations dynamics is, according to the theoretical perspective adopted in this chapter, also one of the key concepts to unlock the real nature of post-bureaucratic organization, beyond the dichotomic approach adopted by post-Weberian studies. Moreover, post-bureaucratic organizations, may be seen also as hybrid organizations (Bergquist, 1994), that are characterized by a high agree of cultural variety. This chapter proposes an integrated theoretical framework, aimed to recompose the apparent incoherent picture of contemporary post-bureaucratic organizations. The present chapter analyses the post-bureaucratic phenomenon, adopting a socio-cultural perspective and post-modern approach. According to the theoretical perspective proposed in this chapter, organizational systems should be considered a specific type of socio - cultural system. The apparent paradox of the dual nature of organizational systems, that may be conceived at the same time as autonomous and as interconnected socio-cultural realities, offers an extraordinary conceptual and methodological challenge for organization studies. The duality of complex organizations dynamics is, according to the theoretical perspective adopted in this chapter, also one of the key concepts to unlock the real nature of post-bureaucratic organization, beyond the dichotomic approach adopted by post-Weberian studies. Moreover, post-bureaucratic organizations, may be seen also as hybrid organizations, that are characterized by a high agree of cultural variety. This chapter proposes an integrated theoretical framework, aimed to recompose the apparent incoherent picture of contemporary post-bureaucratic organizations.