Deisgn automation for analog/mixed-signal (A/MS) circuits and systems is still lagging behind compared to what has been reached in the digital area. As System-on-Chip (SoC) designs include analog components in more cases, these analog parts become even more a bottle neck in the overall design process. The paper is dedicated to latest R&D activities within the MEDEA+ project ANASTASIA+. Main focus will be the development of seamless top-down design methods for integrated analog and misx-signal systems and to achieve a high level of automation and reuse in the A/MS design process. These efforts are motivated by the urgent need to close the current gap in the industrial design flow between system specification and design on the one hand and block-level circuit design on the other hand. The paper will focus on the three subtopics starting with the top-down design flow with applications from circuits sizing, design centering, and automated behaviorial modeling. The next part focuses on modeling and simulation of specific functionalities in sigma-delta design while the last section is dedicated to a mixed-signal System-on-Chip design environment.