diff --git a/DESCRIPTION b/DESCRIPTION
index 463614b..b7a1ea6 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: keedwell
 Title: Latin Squares in R
-Version: 0.1.1.9001
+Version: 0.1.1.9002
 Authors@R: 
     person("Matthew", "Henderson", , "matthew.james.henderson@gmail.com", role = c("aut", "cre"),
            comment = c(ORCID = "0000-0001-7949-8208"))
diff --git a/R/add-rows.R b/R/add-rows.R
index c9da077..cbb53d2 100644
--- a/R/add-rows.R
+++ b/R/add-rows.R
@@ -11,10 +11,11 @@
 #'
 #' @param R latin rectangle
 #' @param rows empty rows to be filled
+#' @param strategy row filling strategy
 #'
-#' @return A latin rectangle with more rows.
+#' @return
 #' @export
-add_rows <- function(R, rows) {
+add_rows <- function(R, rows, strategy = next_row_matching) {
   
   # we assume that the dimension equals
   # the number of columns
@@ -22,16 +23,10 @@ add_rows <- function(R, rows) {
   
   for (i in rows) {
     
-    R <- R |>
-      dplyr::bind_rows(
-        tibble::tibble(
-             row = rep(i, l_order),
-          column = 1:l_order,
-          symbol = next_row(R, l_order)
-        )
-      )
+    R <- strategy(R, i, l_order)
     
   }
   
   return(R)
+
 }
\ No newline at end of file
diff --git a/man/add_rows.Rd b/man/add_rows.Rd
index 36c0675..6df4b35 100644
--- a/man/add_rows.Rd
+++ b/man/add_rows.Rd
@@ -4,15 +4,14 @@
 \alias{add_rows}
 \title{Embed latin rectangle in a latin square}
 \usage{
-add_rows(R, rows)
+add_rows(R, rows, strategy = next_row_matching)
 }
 \arguments{
 \item{R}{latin rectangle}
 
 \item{rows}{empty rows to be filled}
-}
-\value{
-A latin rectangle with more rows.
+
+\item{strategy}{row filling strategy}
 }
 \description{
 Input is a latin rectangle as a data frame with