diff --git a/R/connectivity.R b/R/connectivity.R
index 5d5f7d75..6ac6b758 100644
--- a/R/connectivity.R
+++ b/R/connectivity.R
@@ -1,10 +1,16 @@
 #' @title Get a matrix of connectivities between bodies
 #'
-#' @description  Get an adjacency matrix for the synaptic connectivity within a set of specified bodies
+#' @description  Get an adjacency matrix for the synaptic connectivity within a
+#'   set of specified bodies
+#' @param inputids,outputids identifiers for input and output bodies (use as an
+#'   alternative to \code{bodyids})
 #' @inheritParams neuprint_read_neurons
-#' @return a n x n matrix, where the rows are input neurons and the columns are their targets. Only neurons supplied as the argument
-#' `bodyids` are considered.
-#' @seealso \code{\link{neuprint_fetch_custom}}, \code{\link{neuprint_simple_connectivity}}, \code{\link{neuprint_common_connectivity}}
+#' @return a n x n matrix, where the rows are input neurons and the columns are
+#'   their targets. Only neurons supplied as the argument `bodyids` are
+#'   considered.
+#' @seealso \code{\link{neuprint_fetch_custom}},
+#'   \code{\link{neuprint_simple_connectivity}},
+#'   \code{\link{neuprint_common_connectivity}}
 #' @export
 #' @rdname neuprint_get_adjacency_matrix
 #' @examples
@@ -12,25 +18,43 @@
 #' da2s=neuprint_search(".*DA2.*")
 #' # these will mostly be axo-axonic connections
 #' neuprint_get_adjacency_matrix(da2s$bodyid)
+#'
+#' # rectangular matrix with different in/out neurons
+#' # nb these can be completely different groups
+#' neuprint_get_adjacency_matrix(inputids=da2s$bodyid[1],
+#'   outputids=da2s$bodyid[-1])
 #' }
-neuprint_get_adjacency_matrix <- function(bodyids, dataset = NULL, all_segments = FALSE, conn = NULL, ...){
+neuprint_get_adjacency_matrix <- function(bodyids=NULL, inputids=NULL, outputids=NULL,
+                                          dataset = NULL, all_segments = FALSE, conn = NULL, ...){
+  if(is.null(bodyids)) {
+    if(is.null(inputids) || is.null(outputids))
+      stop("You must either specify bodyids OR (inputids AND outputids)!")
+  } else {
+    if(!is.null(inputids) || !is.null(outputids))
+      stop("You must either specify bodyids OR (inputids AND outputids)!")
+    inputids <- outputids <- bodyids
+  }
+  inputids <- unique(id2char(inputids))
+  outputids <- unique(id2char(outputids))
   all_segments.json = ifelse(all_segments,"Segment","Neuron")
   conn=neuprint_login(conn)
   namefield=neuprint_name_field(conn)
   cypher = sprintf(
     paste(
-      "WITH %s AS input MATCH (n:`%s`)-[c:ConnectsTo]->(m)",
-      "WHERE n.bodyId IN input AND m.bodyId IN input",
+      "WITH %s AS input, %s AS output MATCH (n:`%s`)-[c:ConnectsTo]->(m)",
+      "WHERE n.bodyId IN input AND m.bodyId IN output",
       "RETURN n.bodyId AS upstream, m.bodyId AS downstream, c.weight AS weight, n.%s AS upName, m.%s AS downName"
     ),
-    id2json(bodyids, uniqueids = TRUE),
+    id2json(inputids),
+    id2json(outputids),
     all_segments.json,
     namefield,
     namefield
   )
   nc = neuprint_fetch_custom(cypher=cypher, conn = conn, dataset = dataset, ...)
-  m = matrix(0,nrow = length(bodyids),ncol = length(bodyids))
-  rownames(m) = colnames(m) = bodyids
+  m = matrix(0,nrow = length(inputids),ncol = length(outputids))
+  rownames(m) = inputids
+  colnames(m) = outputids
   for(i in 1:length(nc$data)){
     s = unlist(nc$data[[i]])
     m[as.character(s[1]),as.character(s[2])] = as.numeric(s[3])
diff --git a/man/neuprint_get_adjacency_matrix.Rd b/man/neuprint_get_adjacency_matrix.Rd
index 45ea2b76..0d7344d3 100644
--- a/man/neuprint_get_adjacency_matrix.Rd
+++ b/man/neuprint_get_adjacency_matrix.Rd
@@ -5,7 +5,9 @@
 \title{Get a matrix of connectivities between bodies}
 \usage{
 neuprint_get_adjacency_matrix(
-  bodyids,
+  bodyids = NULL,
+  inputids = NULL,
+  outputids = NULL,
   dataset = NULL,
   all_segments = FALSE,
   conn = NULL,
@@ -15,6 +17,9 @@ neuprint_get_adjacency_matrix(
 \arguments{
 \item{bodyids}{the body IDs for neurons/segments (bodies) you wish to query}
 
+\item{inputids, outputids}{identifiers for input and output bodies (use as an
+alternative to \code{bodyids})}
+
 \item{dataset}{optional, a dataset you want to query. If NULL, the default specified by your R environ file is used. See \code{neuprint_login} for details.}
 
 \item{all_segments}{if TRUE, all bodies are considered, if FALSE, only 'Neurons', i.e. bodies with a status roughly traced status.}
@@ -25,19 +30,28 @@ If NULL, your defaults set in your R.profile or R.environ are used.}
 \item{...}{methods passed to \code{neuprint_login}}
 }
 \value{
-a n x n matrix, where the rows are input neurons and the columns are their targets. Only neurons supplied as the argument
-`bodyids` are considered.
+a n x n matrix, where the rows are input neurons and the columns are
+  their targets. Only neurons supplied as the argument `bodyids` are
+  considered.
 }
 \description{
-Get an adjacency matrix for the synaptic connectivity within a set of specified bodies
+Get an adjacency matrix for the synaptic connectivity within a
+  set of specified bodies
 }
 \examples{
 \donttest{
 da2s=neuprint_search(".*DA2.*")
 # these will mostly be axo-axonic connections
 neuprint_get_adjacency_matrix(da2s$bodyid)
+
+# rectangular matrix with different in/out neurons
+# nb these can be completely different groups
+neuprint_get_adjacency_matrix(inputids=da2s$bodyid[1],
+  outputids=da2s$bodyid[-1])
 }
 }
 \seealso{
-\code{\link{neuprint_fetch_custom}}, \code{\link{neuprint_simple_connectivity}}, \code{\link{neuprint_common_connectivity}}
+\code{\link{neuprint_fetch_custom}},
+  \code{\link{neuprint_simple_connectivity}},
+  \code{\link{neuprint_common_connectivity}}
 }
diff --git a/tests/testthat/test-connectivity.R b/tests/testthat/test-connectivity.R
index 01a7908b..db74751d 100644
--- a/tests/testthat/test-connectivity.R
+++ b/tests/testthat/test-connectivity.R
@@ -12,9 +12,18 @@ test_that("neuprint_connection_table works", {
                                  by.roi = TRUE, roi = "LH(R)"), 'data.frame')
 })
 
-test_that("neuprint_connection_table works", {
+test_that("other connectivity functions work", {
   da2s=neuprint_search(".*DA2.*")
   expect_is(t1 <- neuprint_get_adjacency_matrix(da2s$bodyid), 'matrix')
+  expect_equal(neuprint_get_adjacency_matrix(inputids = da2s$bodyid, outputids = da2s$bodyid),
+               t1)
+  expect_equal(neuprint_get_adjacency_matrix(inputids = da2s$bodyid[1:2],
+                                             outputids = da2s$bodyid[3:5]),
+               t1[1:2,3:5])
+
+  expect_error(neuprint_get_adjacency_matrix(bodyids = da2s$bodyid, outputids = da2s$bodyid))
+  expect_error(neuprint_get_adjacency_matrix(outputids = da2s$bodyid))
+
   expect_equal(colnames(t1), rownames(t1))
   expect_is(t2 <- neuprint_common_connectivity(da2s$bodyid), 'matrix')
   expect_equal(rownames(t1), rownames(t2))