This thesis comprises an introduction, and the text of the Daśarūpa and the Avaloka thereon. In the Introduction I have given an account of the manuscripts selected and cited in the apparatus and have explained the arrangement of text and apparatus. I have also included in the Introduction an outline of the contents of the Daśarūpa and the Avaloka with some critical comments. Dhanañjaya and Dhanika have tried to revive the tātparya theory to explain the function of dhvani. The tātparya theory is arguably the most plausible alternative to the dhvani theory. While Anandavardhana holds Sentiment to be suggestion, Dhanañjaya and Dhanika consider Sentiment to be purport. A relative evaluation of the two theories in the perspective of the analogy of word-sense and sentence-sense has been made to show that the difference between these two theories is one of emphasis. The tātparya theory has been misunderstood and misrepresented by many theorists and did not receive the recognition it deserves. The tacit admission by Anandavardhana that the dhvani theory complements the view of the Mīmāmsakas should ensure the rightful place of the tātparya theory in the wider background of Sanskrit poetics. Dhanañjaya and Dhanika have been influenced by Bhattanāyaka in their interpretation of Bharata’s rasasūtra. And Bhattanāyaka’s interpretation is not very different to that of Abhinavagupta. The controversial question as to whether Dhanañjaya and Dhanika allow Śāntarasa in poetry has also been discussed. The text of the Daśarūpa with the Avaloka commentary has been based on a collation of seven manuscripts and one printed edition.  In constituting the text of the Daśarūpa and the Avaloka thereon, I have, for the most part, chosen the major reading. Occasionally, I have selected a minority reading that explains all variants. A few editorial emendations had to be made. Most of them involve correction of spelling mistakes. All major emendations have been justified by reasons; the reader is of course free to select another reading with the help of the critical apparatus annexed to the text and commentary.