Spoken document segmentation is to automatically set the boundaries between different small topics begin mentioned in long steams of audio signals, and divide the spoken documents into a set of cohesive paragraphs of sentences sharing some common central topic. While spoken document organization aims at automatically analyzing the subject topics of the segmented shot paragraphs of the spoken documents, clustering them into groups with topic labels and organizing them into some hierarchical visual presentation easier for users to browse. Both of them have gained growing attention in the past few years. In the thesis, we explored the use of the Hidden Markov Model (HMM) approach, which has been proven effective for speech recognition and information retrieval, in the context of spoken document segmentation. We not only exploited the lexical information inherent in the spoken document, such as the statistical features or the language model probabilities, but also considered the acoustic information, such as the pause distribution and the confidence measure, in identifying segment boundaries. Moreover, the semantic information conveyed in the spoken document was also integrated into the HMM segmenter for accurately modeling the state observation distributions. On the other hand, we investigated two unsupervised and data-driven organization approaches as well for spoken document analysis, i.e., the Self-Organizing Map (SOM) and Probabilistic Latent Semantic Analysis Map (ProbMap). While for the ProbMap approach, a topical mixture model approach (TMMmap), which came from an alternative perspective, was also studied. A series of experiments was conducted on the Topic Detection and Tracking (TDT) spoken document collections in order to analyze the performance levels of these approaches and compare the differences between them. Finally, we further attempted to incorporate the topic distributions as well as the topological constraints achieved from spoken document organization into the HMM segmenter. Very Promising results were initially demonstrated.