The purpose of this paper is to analyze and describe the relation between knowledge and development in the new knowledge-based economy and to deduct the socio-economic basics of the public marketing strategies in this context. The particularity of this approach is due to the features of knowledge, seen as production factor, mixed public good or global public good, as well as their developments in the context of relationships between university and industry, the new role of public sector research or the new theory of endogenous growth. The economic and social logic of this paper includes marketing among the tools to promote knowledgebased technology progress, imposing even juxtaposition between private or public marketing strategies. The knowledge market develops in specific directions that are compatible and integrated in the development strategies of contemporary economies. Given this context, the quantitative analysis models are inspired by more general or even classical economic models that integrate technical progress, human capital or knowledge status. The main topics discussed in this paper relate to: knowledge and arguments for knowledge marketing development, knowledge and knowledge market as objects of public marketing in contemporary economy, development models that incorporate the impact of knowledge marketing strategies and relevant empirical analysis in the context of the Romanian economy development. The growth methods are based on relevant bibliographic analysis, quantitative models and statistical evaluations, systemic analyses and summaries.