1 Introduction
2 Technical Background
2.1 System Architectures
2.2 GenAI Model Architectures
2.3 Other Generative Models: VAEs, GANs
2.4 Controlling Outputs
2.5 LLM Training
3 The Importance, Challenges, and Desiderata of GenXAI
3.1 Importance of XAI for GenAI
3.2 Why is XAI More Challenging for GenAI?
3.3 Desiderata of Explanations for GenAI
4 Taxonomy of XAI Techniques for GenAI
4.1 Dimensions of Taxonomy
4.2 Classification of Techniques
5 Research Agenda of XAI for GenAI, Discussion and Conclusions