Building Augmented Data to Run Multi-State Models with 'msm' Package R package msmtools version 2.2.1 A fast and general method for restructuring classical longitudinal observational data into augmented transition data suitable for multi-state modeling with the 'msm' package. Works with any longitudinal data where subjects accumulate repeated observations with start and end times and an optional terminal outcome. Methods are described in Grossetti, Ieva and Paganoni (2018) <doi:10.1007/s10729-017-9400-z>. Software Depends: R (>= 4.1) Imports: data.table (>= 1.18.4), cli (>= 3.6.0), msm (>= 1.8.2), survival (>= 3.8-6), ggplot2 (>= 4.0.3) Suggests: testthat (>= 3.3.2), knitr (>= 1.51), rmarkdown (>= 2.31), roxygen2 (>= 8.0.0), patchwork (>= 1.3.2) Francesco Grossetti <francesco.grossetti@unibocconi.it> Comprehensive R Archive Network (CRAN) Francesco Grossetti [aut, cre] (ORCID: <https://orcid.org/0000-0002-5130-7745>) GPL-3 2026-06-08 application/tgz https://CRAN.R-project.org/package=msmtools doi:10.32614/CRAN.package.msmtools