diff --git a/chainforge/react-server/src/App.js b/chainforge/react-server/src/App.js
index b799109..f791ba6 100644
--- a/chainforge/react-server/src/App.js
+++ b/chainforge/react-server/src/App.js
@@ -8,7 +8,7 @@ import ReactFlow, {
 } from 'reactflow';
 import { Button, Menu, LoadingOverlay, Text, Box, List, Loader, Tooltip } from '@mantine/core';
 import { useClipboard } from '@mantine/hooks';
-import { IconSettings, IconTextPlus, IconTerminal, IconCsv, IconSettingsAutomation, IconFileSymlink, IconRobot, IconRuler2 } from '@tabler/icons-react';
+import { IconSettings, IconTextPlus, IconTerminal, IconCsv, IconSettingsAutomation, IconFileSymlink, IconRobot, IconRuler2, IconArrowMerge } from '@tabler/icons-react';
 import RemoveEdge from './RemoveEdge';
 import TextFieldsNode from './TextFieldsNode'; // Import a custom node
 import PromptNode from './PromptNode';
@@ -19,6 +19,7 @@ import ScriptNode from './ScriptNode';
 import AlertModal from './AlertModal';
 import CsvNode from './CsvNode';
 import TabularDataNode from './TabularDataNode';
+import JoinNode from './JoinNode';
 import CommentNode from './CommentNode';
 import GlobalSettingsModal from './GlobalSettingsModal';
 import ExampleFlowsModal from './ExampleFlowsModal';
@@ -87,6 +88,7 @@ const nodeTypes = {
   csv: CsvNode,
   table: TabularDataNode,
   comment: CommentNode,
+  join: JoinNode,
 };
 
 const edgeTypes = {
@@ -197,27 +199,27 @@ const App = () => {
       code = "function evaluate(response) {\n  return response.text.length;\n}";
     addNode({ id: 'evalNode-'+Date.now(), type: 'evaluator', data: { language: progLang, code: code }, position: {x: x-200, y:y-100} });
   };
-  const addVisNode = (event) => {
+  const addVisNode = () => {
     const { x, y } = getViewportCenter();
     addNode({ id: 'visNode-'+Date.now(), type: 'vis', data: {}, position: {x: x-200, y:y-100} });
   };
-  const addInspectNode = (event) => {
+  const addInspectNode = () => {
     const { x, y } = getViewportCenter();
     addNode({ id: 'inspectNode-'+Date.now(), type: 'inspect', data: {}, position: {x: x-200, y:y-100} });
   };
-  const addScriptNode = (event) => {
+  const addScriptNode = () => {
     const { x, y } = getViewportCenter();
     addNode({ id: 'scriptNode-'+Date.now(), type: 'script', data: {}, position: {x: x-200, y:y-100} });
   };
-  const addCsvNode = (event) => {
+  const addCsvNode = () => {
     const { x, y } = getViewportCenter();
     addNode({ id: 'csvNode-'+Date.now(), type: 'csv', data: {}, position: {x: x-200, y:y-100} });
   };
-  const addTabularDataNode = (event) => {
+  const addTabularDataNode = () => {
     const { x, y } = getViewportCenter();
     addNode({ id: 'table-'+Date.now(), type: 'table', data: {}, position: {x: x-200, y:y-100} });
   };
-  const addCommentNode = (event) => {
+  const addCommentNode = () => {
     const { x, y } = getViewportCenter();
     addNode({ id: 'comment-'+Date.now(), type: 'comment', data: {}, position: {x: x-200, y:y-100} });
   };
@@ -225,6 +227,10 @@ const App = () => {
     const { x, y } = getViewportCenter();
     addNode({ id: 'llmeval-'+Date.now(), type: 'llmeval', data: {}, position: {x: x-200, y:y-100} });
   };
+  const addJoinNode = () => {
+    const { x, y } = getViewportCenter();
+    addNode({ id: 'join-'+Date.now(), type: 'join', data: {}, position: {x: x-200, y:y-100} });
+  };
 
   const onClickExamples = () => {
     if (examplesModal && examplesModal.current)
@@ -768,6 +774,11 @@ const App = () => {
               <Menu.Item onClick={addInspectNode} icon={'🔍'}> Inspect Node </Menu.Item>
             </MenuTooltip>
             <Menu.Divider />
+            <Menu.Label>Processors</Menu.Label>
+            <MenuTooltip label="Concatenate responses or input data together before passing into later nodes, within or across variables and LLMs.">
+              <Menu.Item onClick={addJoinNode} icon={<IconArrowMerge size='14pt' />}> Join Node </Menu.Item>
+            </MenuTooltip>
+            <Menu.Divider />
             <Menu.Label>Misc</Menu.Label>
             <MenuTooltip label="Make a comment about your flow.">
               <Menu.Item onClick={addCommentNode} icon={'✏️'}> Comment Node </Menu.Item>
diff --git a/chainforge/react-server/src/JoinNode.js b/chainforge/react-server/src/JoinNode.js
new file mode 100644
index 0000000..7a95d42
--- /dev/null
+++ b/chainforge/react-server/src/JoinNode.js
@@ -0,0 +1,136 @@
+import React, { useState, useEffect } from 'react';
+import { Handle } from 'reactflow';
+import useStore from './store';
+import NodeLabel from './NodeLabelComponent';
+import fetch_from_backend from './fetch_from_backend';
+import { IconArrowMerge } from '@tabler/icons-react';
+import { Divider, NativeSelect, Text } from '@mantine/core';
+
+const JoinNode = ({ data, id }) => {
+
+  let is_fetching = false;
+
+  const [jsonResponses, setJSONResponses] = useState(null);
+
+  const [pastInputs, setPastInputs] = useState([]);
+  const inputEdgesForNode = useStore((state) => state.inputEdgesForNode);
+  const setDataPropsForNode = useStore((state) => state.setDataPropsForNode);
+
+  const handleOnConnect = () => {
+    // For some reason, 'on connect' is called twice upon connection.
+    // We detect when an inspector node is already fetching, and disable the second call:
+    if (is_fetching) return; 
+
+    // Get the ids from the connected input nodes:
+    const input_node_ids = inputEdgesForNode(id).map(e => e.source);
+
+    is_fetching = true;
+
+    // Grab responses associated with those ids:
+    fetch_from_backend('grabResponses', {
+      'responses': input_node_ids
+    }).then(function(json) {
+        if (json.responses && json.responses.length > 0) {
+            setJSONResponses(json.responses);
+        }
+        is_fetching = false;
+    }).catch(() => {
+        is_fetching = false; 
+    });
+  }
+
+  const [groupByVar, setGroupByVar] = useState("all text");
+  const handleChangeGroupByVar = (new_val) => {
+    setGroupByVar(new_val.target.value);
+  };
+
+  const [groupByLLM, setGroupByLLM] = useState("within");
+  const handleChangeGroupByLLM = (new_val) => {
+    setGroupByLLM(new_val.target.value);
+  };
+
+  const [responsesPerPrompt, setResponsesPerPrompt] = useState("all");
+  const handleChangeResponsesPerPrompt = (new_val) => {
+    setResponsesPerPrompt(new_val.target.value);
+  };
+
+  if (data.input) {
+    // If there's a change in inputs...
+    if (data.input != pastInputs) {
+        setPastInputs(data.input);
+        handleOnConnect();
+    }
+  }
+
+  useEffect(() => {
+    if (data.refresh && data.refresh === true) {
+        // Recreate the visualization:
+        setDataPropsForNode(id, { refresh: false });
+        handleOnConnect();
+    }
+  }, [data, id, handleOnConnect, setDataPropsForNode]);
+
+  return (
+    <div className="join-node cfnode">
+    <NodeLabel title={data.title || 'Join Node'} 
+                nodeId={id}
+                icon={<IconArrowMerge size='14pt'/>}
+                />
+    <div style={{display: 'flex', justifyContent: 'left', maxWidth: '100%', marginBottom: '10px'}}>
+      <Text mt='3px' mr='xs'>Join</Text>
+      <NativeSelect onChange={handleChangeGroupByVar}
+                    className='nodrag nowheel'
+                    data={["all text", "by country", "by city"]}
+                    size="xs"
+                    value={groupByVar}
+                    miw='80px'
+                    mr='xs' />
+    </div>
+    <div style={{display: 'flex', justifyContent: 'left', maxWidth: '100%', marginBottom: '10px'}}>
+      <NativeSelect onChange={handleChangeGroupByLLM}
+                    className='nodrag nowheel'
+                    data={["within", "across"]}
+                    size="xs"
+                    value={groupByLLM}
+                    maw='80px'
+                    mr='xs' />
+      <Text mt='3px'>LLM(s)</Text>
+    </div>
+    <div style={{display: 'flex', justifyContent: 'left', maxWidth: '100%'}}>
+      <Text size='sm' mt='3px' mr='xs' color='gray' fs='italic'> take</Text>
+      <NativeSelect onChange={handleChangeResponsesPerPrompt}
+                    className='nodrag nowheel'
+                    data={["all", "1", "2", "3"]}
+                    size="xs"
+                    value={"1"}
+                    maw='80px'
+                    mr='xs' 
+                    color='gray' />
+      <Text size='sm' mt='3px' color='gray' fs='italic'>resp / prompt</Text>
+    </div>
+    <Divider my="xs" label="formatting" labelPosition="center" />
+    <NativeSelect onChange={handleChangeResponsesPerPrompt}
+                  className='nodrag nowheel'
+                  data={["double newline \\n\\n", "newline \\n", "- dashed list", '["list", "of", "strings"]']}
+                  size="xs"
+                  value={"double newline"}
+                  miw='80px' />
+    <Handle
+      type="target"
+      position="left"
+      id="input"
+      className="grouped-handle"
+      style={{ top: "50%" }}
+      onConnect={handleOnConnect}
+    />
+    <Handle
+      type="source"
+      position="right"
+      id="output"
+      className="grouped-handle"
+      style={{ top: "50%" }}
+    />
+  </div>);
+};
+
+export default JoinNode;
\ No newline at end of file
diff --git a/chainforge/react-server/src/text-fields-node.css b/chainforge/react-server/src/text-fields-node.css
index c5fd444..cf15e75 100644
--- a/chainforge/react-server/src/text-fields-node.css
+++ b/chainforge/react-server/src/text-fields-node.css
@@ -531,6 +531,10 @@
     border-color: #222;
   }
 
+  .join-node {
+    min-width: 200px;
+  }
+
   .tabular-data-node {
     min-width: 280px;
   }