diff --git a/R/add.R b/R/add.R
index c463047..02e6c05 100644
--- a/R/add.R
+++ b/R/add.R
@@ -111,6 +111,11 @@ add_custom <- function(base, cmd) {
   glue("{base} {cmd}")
 }
 
+
+add_comment <- function(comment) {
+  paste0("# ", strsplit(comment, "\n")[[1]], collapse = "\n")
+}
+
 switch_them <- function(vec, a, b) {
   what <- vec[a]
   whbt <- vec[b]
diff --git a/R/dockerfile.R b/R/dockerfile.R
index a2f3f98..5f4af37 100644
--- a/R/dockerfile.R
+++ b/R/dockerfile.R
@@ -154,6 +154,13 @@ custom = function(base, cmd) {
 self$Dockerfile <- c(self$Dockerfile, add_custom(base, cmd))
 },
 #' @description
+#' Add a comment.
+#' @param comment The comment to add.
+#' @return the Dockerfile object, invisibly.
+COMMENT = function(comment) {
+self$Dockerfile <- c(self$Dockerfile, add_comment(comment))
+},
+#' @description
 #' Print the Dockerfile.
 #' @return used for side effect
 print = function() {
diff --git a/README.Rmd b/README.Rmd
index a9ff00e..3de4b0f 100644
--- a/README.Rmd
+++ b/README.Rmd
@@ -66,6 +66,12 @@ my_dock <- Dockerfile$new()
 my_dock$MAINTAINER("Colin FAY", "contact@colinfay.me")
 ```
 
+Add comments to your Dockerfile
+
+```{r}
+my_dock$COMMENT("Install required R package.")
+```
+
 Wrap your raw R Code inside the `r()` function to turn it into a bash command with `R -e`.
 
 ```{r}
@@ -75,10 +81,12 @@ my_dock$RUN(r(install.packages("attempt", repo = "http://cran.irsn.fr/")))
 Classical Docker stuffs:
 
 ```{r}
+my_dock$COMMENT("Copy Plumber API and main script to container.")
 my_dock$RUN("mkdir /usr/scripts")
 my_dock$RUN("cd /usr/scripts")
 my_dock$COPY("plumberfile.R", "/usr/scripts/plumber.R")
 my_dock$COPY("torun.R", "/usr/scripts/torun.R")
+my_dock$COMMENT("Expose the API port and run the main script when the container starts.")
 my_dock$EXPOSE(8000)
 my_dock$CMD("Rscript /usr/scripts/torun.R ")
 ```
diff --git a/README.md b/README.md
index 3417e26..d6c693d 100644
--- a/README.md
+++ b/README.md
@@ -60,6 +60,12 @@ my_dock <- Dockerfile$new()
 my_dock$MAINTAINER("Colin FAY", "contact@colinfay.me")
 ```
 
+Add comments to your Dockerfile
+
+``` r
+my_dock$COMMENT("Install required R package.")
+```
+
 Wrap your raw R Code inside the `r()` function to turn it into a bash
 command with `R -e`.
 
@@ -70,10 +76,12 @@ my_dock$RUN(r(install.packages("attempt", repo = "http://cran.irsn.fr/")))
 Classical Docker stuffs:
 
 ``` r
+my_dock$COMMENT("Copy Plumber API and main script to container.")
 my_dock$RUN("mkdir /usr/scripts")
 my_dock$RUN("cd /usr/scripts")
 my_dock$COPY("plumberfile.R", "/usr/scripts/plumber.R")
 my_dock$COPY("torun.R", "/usr/scripts/torun.R")
+my_dock$COMMENT("Expose the API port and run the main script when the container starts.")
 my_dock$EXPOSE(8000)
 my_dock$CMD("Rscript /usr/scripts/torun.R ")
 ```
diff --git a/man/Dockerfile.Rd b/man/Dockerfile.Rd
index 9ab72aa..bd50c9d 100644
--- a/man/Dockerfile.Rd
+++ b/man/Dockerfile.Rd
@@ -40,6 +40,7 @@ my_dock <- Dockerfile$new()
 \item \href{#method-Dockerfile-SHELL}{\code{Dockerfile$SHELL()}}
 \item \href{#method-Dockerfile-MAINTAINER}{\code{Dockerfile$MAINTAINER()}}
 \item \href{#method-Dockerfile-custom}{\code{Dockerfile$custom()}}
+\item \href{#method-Dockerfile-COMMENT}{\code{Dockerfile$COMMENT()}}
 \item \href{#method-Dockerfile-print}{\code{Dockerfile$print()}}
 \item \href{#method-Dockerfile-write}{\code{Dockerfile$write()}}
 \item \href{#method-Dockerfile-switch_cmd}{\code{Dockerfile$switch_cmd()}}
@@ -441,6 +442,26 @@ the Dockerfile object, invisibly.
 }
 }
 \if{html}{\out{<hr>}}
+\if{html}{\out{<a id="method-Dockerfile-COMMENT"></a>}}
+\if{latex}{\out{\hypertarget{method-Dockerfile-COMMENT}{}}}
+\subsection{Method \code{COMMENT()}}{
+Add a comment.
+\subsection{Usage}{
+\if{html}{\out{<div class="r">}}\preformatted{Dockerfile$COMMENT(comment)}\if{html}{\out{</div>}}
+}
+
+\subsection{Arguments}{
+\if{html}{\out{<div class="arguments">}}
+\describe{
+\item{\code{comment}}{The comment to add.}
+}
+\if{html}{\out{</div>}}
+}
+\subsection{Returns}{
+the Dockerfile object, invisibly.
+}
+}
+\if{html}{\out{<hr>}}
 \if{html}{\out{<a id="method-Dockerfile-print"></a>}}
 \if{latex}{\out{\hypertarget{method-Dockerfile-print}{}}}
 \subsection{Method \code{print()}}{
diff --git a/tests/testthat/test-r6.R b/tests/testthat/test-r6.R
index f84bd17..bc0359a 100644
--- a/tests/testthat/test-r6.R
+++ b/tests/testthat/test-r6.R
@@ -45,6 +45,8 @@ test_that("R6 creation works", {
   expect_captured_length(my_dock, 17)
   my_dock$switch_cmd(5, 6)
   expect_captured_length(my_dock, 17)
+  my_dock$COMMENT("Just testing Dockerfile comments.")
+  expect_captured_length(my_dock, 18)
 
   my_dock <- Dockerfile$new(FROM = "plop")
   expect_match(my_dock$Dockerfile, "plop")