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Intracellular transport along cytoskeletal filaments is an essential cellular process that controls numerous cellular functions by promoting correct sorting, transport and delivery of different cargos in the cell. The microtubule system and associated molecular motors, dynein and kinesins, are essential components of this process, and their tight regulation is required to ensure the precise spatio-temporal distribution of cargos. In this thesis, we dissect the mechanisms underlying cargo selection and cargo transport by microtubule motors and adaptor proteins and investigate possible connections between the docking and fusion machineries essential for the delivery of cellular content into the extracellular space. In chapter 1, we introduce molecular motors and focus on the current knowledge on the organization of microtubule-based transport. The role of adaptor proteins in controlling cargo selection and motor activity is investigated in chapter 2, where we demonstrate that the adaptor protein BICD2 forms a triple complex with the dynein-dynactin complex and promotes a stable interaction between dynein and dynactin. Additionally, we provide evidence for the requirement of this triple stable complex for dynein activation and show that the interaction between dynein, dynactin and LIS1 is required for the BICD2-mediated recruitment of the dynein complex to cellular structures. In chapter 3, we investigate the role of different kinesins and adaptor proteins in the transport of Rab6-positive secretory vesicles. We demonstrate that kinesin-1 and kinesin-3 differently influence the speed of transport of Rab6 vesicles. Additionally, we demonstrate that the Bicaudal D family proteins BICD2 and BICDR-1 differentially regulate the velocity of dynein-based movements. We show that BICDR-1 increases the velocity of transport of secretory vesicles towards microtubule minus ends and thereby controls the distribution of cellular cargos. In chapter 4, we show that kinesin-3 family member KIF13B promotes the transport of constitutive secretory vesicles to the periphery of the cell. Additionally, we analyze the distribution of KIF13B on single Rab6 vesicles during active transport, a promising system to study multimotor transport mechanisms in the context of the cell. In chapter 5, we demonstrate that KIDINS220, a novel KIF13B-interacting protein, links KIF13B to the Dystrophin-Associated Protein Complex (DAPC) and provide evidence for the presence of this complex at cortical structures in proximity of focal adhesions. Based on these results, we discuss the possible role for the KIF13B-DAPC complex in podosomes and neurons. In chapter 6, we investigate the molecular link between the docking and fusion machineries for Rab6 vesicles. We found that the SNARE proteins VAMP4 and SNAP29 are involved in the fusion of Rab6 vesicles with the plasma membrane. Additionally, we propose a new function for the EHD endocytic family in the exocytosis of carriers of constitutive secretion. In chapter 7, we discuss the general implications of our findings and the possible strategies for future experiments.