diff --git a/NAMESPACE b/NAMESPACE
index eb27c9fe..c3da2363 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -1,5 +1,6 @@
 # Generated by roxygen2: do not edit by hand
 
+S3method(summary,wlr)
 export(counting_process)
 export(create_cut)
 export(create_test)
diff --git a/man/summary.Rd b/man/summary.Rd
new file mode 100644
index 00000000..97a65559
--- /dev/null
+++ b/man/summary.Rd
@@ -0,0 +1,84 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/summary.R
+\name{summary.wlr}
+\alias{summary.wlr}
+\title{Summary of group sequential simulations.}
+\usage{
+\method{summary}{wlr}(simulation, design, title, subtitle, ...)
+}
+\arguments{
+\item{simulation}{Simulation results generated by \code{\link[=sim_gs_n]{sim_gs_n()}}}
+
+\item{design}{Asymptotic design generated by \code{\link[gsDesign2:gs_design_ahr]{gsDesign2::gs_design_ahr()}},
+\code{\link[gsDesign2:gs_power_ahr]{gsDesign2::gs_power_ahr()}}, \code{\link[gsDesign2:gs_design_wlr]{gsDesign2::gs_design_wlr()}}, or \link[gsDesign2:gs_power_wlr]{gsDesign2::gs_power_wlr}.}
+
+\item{title}{Title of the gt table.}
+
+\item{subtitle}{Subtitle of the gt table.}
+
+\item{...}{Additional parameters (not used).}
+}
+\value{
+A gt table
+}
+\description{
+Summary of group sequential simulations.
+}
+\examples{
+library(gsDesign2)
+
+# Parameters for enrollment
+enroll_rampup_duration <- 4 # Duration for enrollment ramp up
+enroll_duration <- 16 # Total enrollment duration
+enroll_rate <- define_enroll_rate(
+  duration = c(
+    enroll_rampup_duration, enroll_duration - enroll_rampup_duration),
+ rate = c(10, 30))
+
+# Parameters for treatment effect
+delay_effect_duration <- 3 # Delay treatment effect in months
+median_ctrl <- 9 # Survival median of the control arm
+median_exp <- c(9, 14) # Survival median of the experimental arm
+dropout_rate <- 0.001
+fail_rate <- define_fail_rate(
+  duration = c(delay_effect_duration, 100),
+  fail_rate = log(2) / median_ctrl,
+  hr = median_ctrl / median_exp,
+  dropout_rate = dropout_rate)
+
+# Other related parameters
+alpha <- 0.025 # Type I error
+beta <- 0.1 # Type II error
+ratio <- 1 # Randomization ratio (experimental:control)
+
+# Build a one-sided group sequential design
+design <- gs_design_ahr(
+  enroll_rate = enroll_rate, fail_rate = fail_rate,
+  ratio = ratio, alpha = alpha, beta = beta,
+  analysis_time = c(12, 24, 36),
+  upper = gs_spending_bound,
+  upar = list(sf = gsDesign::sfLDOF, total_spend = alpha),
+  lower = gs_b,
+  lpar = rep(-Inf, 3))
+
+# Define cuttings of 2 IAs and 1 FA
+ia1_cut <- create_cut(target_event_overall = ceiling(design$analysis$event[1]))
+ia2_cut <- create_cut(target_event_overall = ceiling(design$analysis$event[2]))
+fa_cut <- create_cut(target_event_overall = ceiling(design$analysis$event[3]))
+
+# Run simulations
+simulation <- sim_gs_n(
+  n_sim = 3,
+  sample_size = ceiling(design$analysis$n[3]),
+  enroll_rate = design$enroll_rate,
+  fail_rate = design$fail_rate,
+  test = wlr,
+  cut = list(ia1 = ia1_cut, ia2 = ia2_cut, fa = fa_cut),
+  weight = fh(rho = 0, gamma = 0.5))
+
+# Summarize simulations
+simulation |>
+  summary(design = design,
+          title = "Comparison of simulation and asymptotic calculation",
+          subtitle = "WLR-FH(0, 0.5)")
+}