Herpesvirus envelopment is assumed to follow an uneconomical pathway including primary envelopment at the inner nuclear membrane, de-envelopment at the outer nuclear membrane, and reenvelopment at the trans-Golgi network. In contrast to the hypothesis of de-envelopment by fusion of the primary envelope with the outer nuclear membrane, virions were demonstrated to be transported from the perinuclear space to rough endoplasmic reticulum (RER) cisternae. Here we show by high-resolution microscopy that herpes simplex virus 1 envelopment follows two diverse pathways. First, nuclear envelopment includes budding of capsids at the inner nuclear membrane into the perinuclear space whereby tegument and a thick electron dense envelope are acquired. The substance responsible for the dense envelope is speculated to enable intraluminal transportation of virions via RER into Golgi cisternae. Within Golgi cisternae, virions are packaged into transport vacuoles containing one or several virions. Second, for cytoplasmic envelopment, capsids gain direct access from the nucleus to the cytoplasm via impaired nuclear pores. Cytoplasmic capsids could bud at the outer nuclear membrane, at membranes of RER, Golgi cisternae, and large vacuoles, and at banana-shaped membranous entities that were found to continue into Golgi membranes. Envelopes originating by budding at the outer nuclear membrane and RER membrane also acquire a dense substance. Budding at Golgi stacks, designated wrapping, results in single virions within small vacuoles that contain electron-dense substances between envelope and vacuolar membranes.Much controversy has arisen about the pathway of herpesvirus capsids from their nuclear origin to the site of their release into the extracellular space (e.g., see references 4, 13, 19, 50, 52, 53, 55, and 56). The current widely accepted view suggests the formation of primary virions comprising capsid, primary tegument, and a primary envelope that originates by budding at the inner nuclear membrane into the perinuclear space (37). For de-envelopment, the primary envelope is assumed to be inserted into the outer nuclear membrane by fusion, releasing capsid and the primary tegument into the cytoplasm (14). In contrast to de-envelopment, many investigations clearly demonstrate that "primary" virions are transported from the perinuclear space into rough endoplasmic reticulum (RER) cisternae (12,15,45,51,52,58,62) and that "primary" wild-type virions can accumulate within the perinuclear space-RER compartment (55). Intraluminal accumulations of virions have also been explained as a failure in deenvelopment, e.g., due to the lack of US3 protein in pseudorabies virus (25). The de-envelopment theory also does not consider that membrane fusion is a fast but well-studied process starting by close apposition of the membranes to allow fusion followed by pore formation (24,27,32,36). Recognizing close apposition and pore formation is imperative to distinguishing fusion from budding and fission. To our knowledge, pore formation between "prim...