diff --git a/output/timetable.js b/output/timetable.js
index e7e36e4..cda2676 100644
--- a/output/timetable.js
+++ b/output/timetable.js
@@ -273,10 +273,13 @@ if (shifts.size < 1) {
 
 oshifts = Array.from(shifts).sort()
 
-$("body").append("<div><button id='show-colour-diff'>Show colour diff</button><table class='tsummary'></table></div>")
+$("body").append("<div><button id='show-colour-diff'>Show colour diff</button><button id='toggle-prior-adjust' style='margin-left:10px;'>Toggle Prior Adjust</button><table class='tsummary'></table></div>")
 $("#show-colour-diff").on("click", (evt) => {
     $("table.tsummary").find(`td.target-assigned`).toggleClass("no-colour");
 });
+$("#toggle-prior-adjust").on("click", (evt) => {
+    $("table.tsummary").find(`td.prior-adjust, th.prior-adjust-col`).toggle();
+});
 
 $("table.tsummary").append("<tr class='header'></tr>");
 h = $("table.tsummary tr.header");
@@ -291,6 +294,9 @@ oshifts.forEach((s) => {
 
 });
 
+// Column for prior-adjustment (hidden by default)
+h.append(`<th class='prior-adjust-col' style='display:none'>Prior Adjust</th>`);
+
 
 
 $(".table-div .worker-row .worker").each((n, tr) => {
@@ -332,6 +338,36 @@ $(".table-div .worker-row .worker").each((n, tr) => {
         }
     })
 
+    // Build per-shift prior-adjust spans from data-previous-shifts
+    let prev_attr = jtr.attr("data-previous-shifts");
+    let partsHtml = "";
+    if (prev_attr) {
+        try {
+            let prev_map = (typeof prev_attr === 'object') ? prev_attr : JSON.parse(prev_attr);
+            let parts = [];
+            for (let k in prev_map) {
+                if (!prev_map.hasOwnProperty(k)) continue;
+                let entry = prev_map[k];
+                let adj = null;
+                if (entry && typeof entry === 'object') {
+                    if ('adjustment' in entry) adj = parseFloat(entry.adjustment);
+                    else if ('allocated' in entry && 'worked' in entry) adj = parseFloat(entry.allocated) - parseFloat(entry.worked);
+                } else if (Array.isArray(entry) && entry.length >= 2) {
+                    adj = parseFloat(entry[1]) - parseFloat(entry[0]);
+                }
+                if (adj && Math.abs(adj) > 0.0001) {
+                    let s = (adj > 0 ? '+' : '') + Number(adj).toFixed(2);
+                    // span includes data attributes for per-shift colouring later
+                    partsHtml += `<span class='prior-adjust-part' data-shift='${k}' data-adj='${adj}' style='display:inline-block;padding:0 6px;margin-right:6px;border-radius:3px'>${k}:${s}</span>`;
+                }
+            }
+        } catch (e) {
+            // ignore parse errors
+        }
+    }
+
+    row.append(`<td class='prior-adjust' style='display:none'>${partsHtml}</td>`)
+
     $("table.tsummary").append(row)
 })
 
@@ -380,6 +416,31 @@ oshifts.forEach((shift) => {
 
 });
 
+// Colour each per-shift prior-adjust span independently.
+// For each shift, find the maximum absolute adjustment across rows and scale saturation accordingly.
+let priorShiftMax = {};
+$("table.tsummary").find("td.prior-adjust .prior-adjust-part").each((n, span) => {
+    let $span = $(span);
+    let shift = $span.attr('data-shift');
+    let adj = parseFloat($span.attr('data-adj')) || 0;
+    let absadj = Math.abs(adj);
+    if (!(shift in priorShiftMax)) priorShiftMax[shift] = 0;
+    priorShiftMax[shift] = Math.max(priorShiftMax[shift], absadj);
+});
+
+// Apply colouring to each span using hsv2rgb (green for positive, red for negative)
+$("table.tsummary").find("td.prior-adjust .prior-adjust-part").each((n, span) => {
+    let $span = $(span);
+    let shift = $span.attr('data-shift');
+    let adj = parseFloat($span.attr('data-adj')) || 0;
+    if (Math.abs(adj) < 1e-9) return;
+    let max = priorShiftMax[shift] || Math.abs(adj) || 1;
+    let sat = (max === 0) ? 1 : Math.min(1, Math.abs(adj) / max);
+    let hue = (adj > 0) ? 120 : 0; // green or red
+    $span.css({ backgroundColor: hsv2rgb(hue, sat, 1), color: '#000' });
+    $span.addClass('no-colour');
+});
+
 let selectedShifts = new Set();
 
 let shiftColors = {};
diff --git a/rota_generator/shifts.py b/rota_generator/shifts.py
index 459bd62..04899cd 100644
--- a/rota_generator/shifts.py
+++ b/rota_generator/shifts.py
@@ -4898,10 +4898,35 @@ class RotaBuilder(object):
                             sun_count += 1
                             break
             # Small HTML summary to be inserted inside the worker td (friendly display)
+            # Build a small adjustments summary from prior allocations (if any)
+            prior_map = {}
+            adjustments_list = []
+            for shift in self.get_shifts():
+                prev = getattr(worker, "previous_shifts", {}) or {}
+                if shift.name in prev:
+                    worked, allocated = prev[shift.name]
+                    try:
+                        adj = float(allocated) - float(worked)
+                    except Exception:
+                        adj = 0.0
+                    prior_map[shift.name] = {"worked": worked, "allocated": allocated, "adjustment": adj}
+                    if adj != 0:
+                        adjustments_list.append(f"{shift.name}:{adj:+g}")
+
+            adjustments_html = ""
+            if adjustments_list:
+                adjustments_html = (
+                    "<div class='worker-adjustments auto-generated' style='margin-top:3px; font-size:0.85em; color:#666;'>"
+                    + "Adjust: "
+                    + ", ".join(adjustments_list)
+                    + "</div>"
+                )
+
             worker_summary_html = (
                 f"<div class='worker-summary auto-generated' style='margin-top:4px; font-size:0.9em; color:#333;'>"
                 f"<span class=\'weekend-sat\'>Sat: <strong>{sat_count}</strong></span>"
                 f" &nbsp; <span class=\'weekend-sun\'>Sun: <strong>{sun_count}</strong></span>"
+                f"{adjustments_html}"
                 f"</div>"
             )
 
@@ -4922,6 +4947,7 @@ class RotaBuilder(object):
             data-bank-holiday-extra='{bank_holiday_extra}'
             data-weekend-sat='{weekend_sat}'
             data-weekend-sun='{weekend_sun}'
+            data-previous-shifts='{previous_shifts}'
             data-shift-diff='{shift_diff}'
             data-shift-diff-summed='{shift_diff_summed}'
             >
@@ -4944,6 +4970,7 @@ class RotaBuilder(object):
                 weekend_sat=sat_count,
                 weekend_sun=sun_count,
                 worker_summary_html=worker_summary_html,
+                previous_shifts=json.dumps(prior_map),
                 pair=worker.pair,
                 shift_balance_extra=json.dumps(worker.shift_balance_extra),
                 shift_diff=json.dumps(shift_diff_dict),