diff --git a/R/measure_features.R b/R/measure_features.R
index 608d6fc..b570b3e 100644
--- a/R/measure_features.R
+++ b/R/measure_features.R
@@ -150,6 +150,7 @@ net_by_richclub <- function(.data){
 net_by_factions <- function(.data,
                        membership = NULL){
   .data <- manynet::expect_nodes(.data)
+  membership <- .resolve_membership(.data, membership)
   if(is.null(membership)){
     manynet::snet_info("No membership vector assigned.",
               "Partitioning the network using {.fn node_in_partition}.")
@@ -207,6 +208,7 @@ net_by_modularity <- function(.data,
                              membership = NULL, 
                              resolution = 1){
   .data <- manynet::expect_nodes(.data)
+  membership <- .resolve_membership(.data, membership)
   if(is.null(membership)){
     manynet::snet_info("Since no membership argument has been provided,",
               "a partition of the network into two will be calculated and used.")
diff --git a/R/motif_brokerage.R b/R/motif_brokerage.R
index 7588b9a..8813b1f 100644
--- a/R/motif_brokerage.R
+++ b/R/motif_brokerage.R
@@ -33,15 +33,16 @@ NULL
 node_x_brokerage <- function(.data, membership, standardized = FALSE){
   thisRequires("sna")
   .data <- manynet::expect_nodes(.data)
+  membership <- .resolve_membership(.data, membership)
   if(!manynet::is_twomode(.data)){
     out <- sna::brokerage(manynet::as_network(.data),
-                          manynet::node_attribute(.data, membership))
+                          membership)
     out <- if(standardized) out$z.nli else out$raw.nli
     colnames(out) <- c("Coordinator", "Itinerant", "Gatekeeper", 
                        "Representative", "Liaison", "Total")
   } else {
     out <- suppressWarnings(sna::brokerage(manynet::as_network(manynet::to_mode1(.data)),
-                                           manynet::node_attribute(.data, membership)))
+                                           membership))
     out <- if(standardized) out$z.nli else out$raw.nli
     out <- out[,-4]
     colnames(out) <- c("Coordinator", "Itinerant", "Gatekeeper", 
@@ -72,15 +73,16 @@ NULL
 net_x_brokerage <- function(.data, membership, standardized = FALSE){
   thisRequires("sna")
   .data <- manynet::expect_nodes(.data)
+  membership <- .resolve_membership(.data, membership)
   if(!manynet::is_twomode(.data)){
     out <- sna::brokerage(manynet::as_network(.data),
-                          manynet::node_attribute(.data, membership))
+                          membership)
     out <- if(standardized) out$z.gli else out$raw.gli
     names(out) <- c("Coordinator", "Itinerant", "Gatekeeper", 
                     "Representative", "Liaison", "Total")
   } else {
     out <- suppressWarnings(sna::brokerage(manynet::as_network(manynet::to_mode1(.data)),
-                                           manynet::node_attribute(.data, membership)))
+                                           membership))
     out <- if(standardized) out$z.gli else out$raw.gli
     names(out) <- c("Coordinator", "Itinerant", "Gatekeeper", 
                     "Representative", "Liaison", "Total")
@@ -118,10 +120,11 @@ node_by_brokering_activity <- function(.data, membership){
   .data <- manynet::expect_nodes(.data)
   twopaths <- .to_twopaths(.data)
   if(!missing(membership)){
-    twopaths$from_memb <- manynet::node_attribute(.data, membership)[`if`(manynet::is_labelled(.data),
+    membership <- .resolve_membership(.data, membership)
+    twopaths$from_memb <- membership[`if`(manynet::is_labelled(.data),
                                                                           match(twopaths$from, manynet::node_names(.data)),
                                                                           twopaths$from)]
-    twopaths$to_memb <- manynet::node_attribute(.data, membership)[`if`(manynet::is_labelled(.data),
+    twopaths$to_memb <- membership[`if`(manynet::is_labelled(.data),
                                                                         match(twopaths$to.y, manynet::node_names(.data)),
                                                                         twopaths$to.y)]
     twopaths <- dplyr::filter(twopaths, from_memb != to_memb)
@@ -147,10 +150,11 @@ node_by_brokering_exclusivity <- function(.data, membership){
   .data <- manynet::expect_nodes(.data)
   twopaths <- .to_twopaths(.data)
   if(!missing(membership)){
-    twopaths$from_memb <- manynet::node_attribute(.data, membership)[`if`(manynet::is_labelled(.data),
+    membership <- .resolve_membership(.data, membership)
+    twopaths$from_memb <- membership[`if`(manynet::is_labelled(.data),
                                                                           match(twopaths$from, manynet::node_names(.data)),
                                                                           twopaths$from)]
-    twopaths$to_memb <- manynet::node_attribute(.data, membership)[`if`(manynet::is_labelled(.data),
+    twopaths$to_memb <- membership[`if`(manynet::is_labelled(.data),
                                                                         match(twopaths$to.y, manynet::node_names(.data)),
                                                                         twopaths$to.y)]
     twopaths <- dplyr::filter(twopaths, from_memb != to_memb)
diff --git a/R/netrics-utils.R b/R/netrics-utils.R
index a97ab23..55057ff 100644
--- a/R/netrics-utils.R
+++ b/R/netrics-utils.R
@@ -40,4 +40,16 @@ seq_nodes <- function(.data){
   seq.int(manynet::net_nodes(.data))
 }
 
+# Resolve membership to a vector:
+# if a single character string naming a network attribute is provided,
+# retrieve that attribute as a vector; otherwise return the value as-is.
+.resolve_membership <- function(.data, membership) {
+  if (is.character(membership) && length(membership) == 1 &&
+      membership %in% manynet::node_attribute_names(.data)) {
+    manynet::node_attribute(.data, membership)
+  } else {
+    membership
+  }
+}
+
 # nocov end
\ No newline at end of file
diff --git a/man-roxygen/param_memb.R b/man-roxygen/param_memb.R
index 991f2d7..37f307c 100644
--- a/man-roxygen/param_memb.R
+++ b/man-roxygen/param_memb.R
@@ -1,5 +1,6 @@
-#' @param membership A character vector of categorical membership.
-#'   This is a vector of the same length as the number of nodes in the network,
-#'   where each element is a character string indicating the membership of the corresponding node.
-#'   While this may often be a vector created using `node_in_*()` functions, 
+#' @param membership A character string naming an existing node attribute in
+#'   the network, or a categorical vector of the same length as the number of
+#'   nodes in the network where each element indicates the group membership of
+#'   the corresponding node.
+#'   While this may often be a vector created using `node_in_*()` functions,
 #'   it can be any character vector that assigns nodes to groups or categories.